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Li L, Wang J, Liu YJ, Zhou XL, Huang DY, Shen ZM, He SJ, Liu ZD, Li CF, Guo GC. Experimental realization of multiple frequency photoassociation in an optical dipole trap. J Chem Phys 2024; 161:144301. [PMID: 39377324 DOI: 10.1063/5.0226482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2024] [Accepted: 09/23/2024] [Indexed: 10/09/2024] Open
Abstract
The generation of cold molecules is an important topic in the field of cold atoms and molecules and has received relevant advanced research attention in ultracold chemistry, quantum computation, and quantum metrology. With a high atomic phase space density, optical dipole traps have been widely used to prepare, trap, and study cold molecules. In this work, Rb2 molecules were photoassociated in a magneto-optical trap to obtain a precise rovibrational spectrum, which provided accurate numerical references for the realization of multiple frequency photoassociation. By meeting the harsh requirements of photoassociation in optical dipole traps, the cold molecule photoassociation process was well explored, and different photoassociation resonances were simultaneously addressed in a single optical dipole trap. This method can be universally extended to simultaneously photoassociate cold molecules with different internal states or atomic species in a single optical dipole trap, thus advancing generous cold molecule studies such as cold molecule collision dynamics.
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Affiliation(s)
- Li Li
- CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Quantum Network, University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Jian Wang
- CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Quantum Network, University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Yi-Jia Liu
- CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Quantum Network, University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Xiao-Long Zhou
- CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Quantum Network, University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Dong-Yu Huang
- CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Quantum Network, University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, China
| | - Ze-Min Shen
- CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Quantum Network, University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Si-Jian He
- CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Quantum Network, University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Zhao-Di Liu
- CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Quantum Network, University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
| | - Chuan-Feng Li
- CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Quantum Network, University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, China
| | - Guang-Can Guo
- CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, China
- Anhui Province Key Laboratory of Quantum Network, University of Science and Technology of China, Hefei 230026, People's Republic of China
- CAS Center For Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, China
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Morita M, Brumer P, Tscherbul TV. Multichannel Quantum Defect Theory with a Frame Transformation for Ultracold Atom-Molecule Collisions in Magnetic Fields. PHYSICAL REVIEW LETTERS 2024; 133:093402. [PMID: 39270161 DOI: 10.1103/physrevlett.133.093402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 04/13/2024] [Accepted: 07/11/2024] [Indexed: 09/15/2024]
Abstract
We extend the powerful formalism of multichannel quantum defect theory combined with a frame transformation to ultracold atom-molecule collisions in magnetic fields. By solving the coupled-channel equations with hyperfine and Zeeman interactions omitted at short range, the extended theory enables a drastically simplified description of the intricate quantum dynamics of ultracold molecular collisions in terms of a small number of short-range parameters. We apply the formalism to ultracold Mg+NH collisions in a magnetic field, achieving a 10^{4}-fold reduction in computational effort.
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Affiliation(s)
- Masato Morita
- Chemical Physics Theory Group, Department of Chemistry, and Center for Quantum Information and Quantum Control, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Paul Brumer
- Chemical Physics Theory Group, Department of Chemistry, and Center for Quantum Information and Quantum Control, University of Toronto, Toronto, Ontario M5S 3H6, Canada
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3
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Ding Y, Greenman L, Rolles D. Surface hopping molecular dynamics simulation of ultrafast methyl iodide photodissociation mapped by Coulomb explosion imaging. Phys Chem Chem Phys 2024; 26:22423-22432. [PMID: 39140357 DOI: 10.1039/d4cp01679c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
We present a highly efficient approach to directly and reliably simulate photodissociation followed by Coulomb explosion of methyl iodide. In order to achieve statistical reliability, more than 40 000 trajectories are calculated on accurate potential energy surfaces of both the neutral molecule and the doubly charged cation. Non-adiabatic effects during photodissociation are treated using a Landau-Zener surface hopping algorithm. The simulation is performed analogous to a recent pump-probe experiment using coincident ion momentum imaging [Ziaee et al., Phys. Chem. Chem. Phys., 2023, 25, 9999-10010]. At large pump-probe delays, the simulated delay-dependent kinetic energy release signals show overall good agreement with the experiment, with two major dissociation channels leading to I(2P3/2) and I*(2P1/2) products. At short pump-probe delays, the simulated kinetic energy release differs significantly from the values obtained by a purely Coulombic approximation or a one-dimensional description of the dicationic potential energy surfaces, and shows a clear bifurcation near 12 fs, owing to non-adiabatic transitions through a conical intersection. The proposed approach is particularly suitable and efficient in simulating processes that highly rely on statistics or for identifying rare reaction channels.
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Affiliation(s)
- Yijue Ding
- J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA.
| | - Loren Greenman
- J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA.
| | - Daniel Rolles
- J. R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, KS 66506, USA.
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Doronin IV, Zyablovsky AA, Andrianov ES, Kalmykov AS, Gritchenko AS, Khlebtsov BN, Wang SP, Kang B, Balykin VI, Melentiev PN. Quantum engineering of the radiative properties of a nanoscale mesoscopic system. NANOSCALE 2024; 16:14899-14910. [PMID: 39040019 DOI: 10.1039/d4nr01233j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
Despite the recent advances in quantum technology, the problem of controlling the light emission properties of quantum emitters used in numerous applications remains: a large spectral width, low intensity, blinking, photodegradation, biocompatibility, etc. In this work, we present the theoretical and experimental investigation of quantum light sources - mesoscopic systems consisting of fluorescent molecules in a thin polydopamine layer coupled with metallic or dielectric nanoparticles. Polydopamines possess many attractive adhesive and optical properties that promise their use as host media for dye molecules. However, numerous attempts to incorporate fluorescent molecules into polydopamines have failed, as polydopamine has been shown to be a very efficient fluorescence quencher through Förster resonance energy transfer and/or photoinduced electron transfer. Using the system as an example, we demonstrate new insights into the interactions between molecules and electromagnetic fields by carefully shaping its energy levels through strong matter-wave coupling of molecules to metallic nanoparticles. We show that the strong coupling effectively suppresses the quenching of fluorescent molecules in polydopamine, opening new possibilities for imaging.
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Affiliation(s)
- I V Doronin
- Moscow Institute of Physics and Technology, Moscow, Russia
| | - A A Zyablovsky
- Moscow Institute of Physics and Technology, Moscow, Russia
- Institute for Theoretical and Applied Electromagnetics, Kotelnikov Institute of Radioengineering and Electronics of Russian Academy of Sciences, Moscow, Russia
| | - E S Andrianov
- Moscow Institute of Physics and Technology, Moscow, Russia
- Institute for Theoretical and Applied Electromagnetics, Moscow, Russia
| | - A S Kalmykov
- Institute of Spectroscopy RAS, Moscow, Troitsk 108840, Russia
| | - A S Gritchenko
- Institute of Spectroscopy RAS, Moscow, Troitsk 108840, Russia
| | - B N Khlebtsov
- Institute of Biochemistry and Physiology of Plants and Microorganisms, Saratov Scientific Centre of the Russian Academy of Sciences, Saratov, Russia
| | - S-P Wang
- State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, 163 Xianlin Road, Nanjing 210023, P. R. China
| | - Bin Kang
- State Key Laboratory of Analytical Chemistry for Life Science and Collaborative Innovation Center of Chemistry for Life Sciences, School of Chemistry and Chemical Engineering, Nanjing University, 163 Xianlin Road, Nanjing 210023, P. R. China
| | | | - Pavel N Melentiev
- Institute of Spectroscopy RAS, Moscow, Troitsk 108840, Russia
- National Research University, Moscow, Russia.
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Arrowsmith-Kron G, Athanasakis-Kaklamanakis M, Au M, Ballof J, Berger R, Borschevsky A, Breier AA, Buchinger F, Budker D, Caldwell L, Charles C, Dattani N, de Groote RP, DeMille D, Dickel T, Dobaczewski J, Düllmann CE, Eliav E, Engel J, Fan M, Flambaum V, Flanagan KT, Gaiser AN, Garcia Ruiz RF, Gaul K, Giesen TF, Ginges JSM, Gottberg A, Gwinner G, Heinke R, Hoekstra S, Holt JD, Hutzler NR, Jayich A, Karthein J, Leach KG, Madison KW, Malbrunot-Ettenauer S, Miyagi T, Moore ID, Moroch S, Navratil P, Nazarewicz W, Neyens G, Norrgard EB, Nusgart N, Pašteka LF, N Petrov A, Plaß WR, Ready RA, Pascal Reiter M, Reponen M, Rothe S, Safronova MS, Scheidenerger C, Shindler A, Singh JT, Skripnikov LV, Titov AV, Udrescu SM, Wilkins SG, Yang X. Opportunities for fundamental physics research with radioactive molecules. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2024; 87:084301. [PMID: 38215499 DOI: 10.1088/1361-6633/ad1e39] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 01/12/2024] [Indexed: 01/14/2024]
Abstract
Molecules containing short-lived, radioactive nuclei are uniquely positioned to enable a wide range of scientific discoveries in the areas of fundamental symmetries, astrophysics, nuclear structure, and chemistry. Recent advances in the ability to create, cool, and control complex molecules down to the quantum level, along with recent and upcoming advances in radioactive species production at several facilities around the world, create a compelling opportunity to coordinate and combine these efforts to bring precision measurement and control to molecules containing extreme nuclei. In this manuscript, we review the scientific case for studying radioactive molecules, discuss recent atomic, molecular, nuclear, astrophysical, and chemical advances which provide the foundation for their study, describe the facilities where these species are and will be produced, and provide an outlook for the future of this nascent field.
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Affiliation(s)
- Gordon Arrowsmith-Kron
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, United States of America
| | - Michail Athanasakis-Kaklamanakis
- Experimental Physics Department, CERN, CH-1211 Geneva 23, Switzerland
- KU Leuven, Department of Physics and Astronomy, Instituut voor Kern- en Stralingsfysica, B-3001 Leuven, Belgium
| | - Mia Au
- CERN, Geneva, Switzerland
- Johannes Gutenberg-Universität Mainz, Mainz, Germany
| | - Jochen Ballof
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, United States of America
- Accelerator Systems Department, CERN, 1211 Geneva 23, Switzerland
| | - Robert Berger
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Anastasia Borschevsky
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Groningen, The Netherlands
| | - Alexander A Breier
- Institute of Physics, University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany
| | | | - Dmitry Budker
- Helmholtz-Institut, GSI Helmholtzzentrum fur Schwerionenforschung and Johannes Gutenberg University, Mainz 55128, Germany
- Department of Physics, University of California at Berkeley, Berkeley, CA 94720-7300, United States of America
| | - Luke Caldwell
- JILA, NIST and University of Colorado, Boulder, CO 80309, United States of America
- Department of Physics, University of Colorado, Boulder, CO 80309, United States of America
| | - Christopher Charles
- TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3, Canada
- University of Western Ontario, 1151 Richmond St. N., London, Ontario N6A 5B7, Canada
| | - Nike Dattani
- HPQC Labs, Waterloo, Ontario, Canada
- HPQC College, Waterloo, Ontario, Canada
| | - Ruben P de Groote
- Instituut voor Kern- en Stralingsfysica, KU Leuven, Leuven, Belgium
- Department of Physics, University of Jyväskylä, Jyväskylä, Finland
| | - David DeMille
- University of Chicago, Chicago, IL, United States of America
- Argonne National Laboratory, Lemont, IL, United States of America
| | - Timo Dickel
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- II. Physikalisches Institut, Justus-Liebig-Universität Gießen, 35392 Gießen, Germany
| | - Jacek Dobaczewski
- School of Physics, Engineering and Technology, University of York, Heslington, York YO10 5DD, United Kingdom
- Institute of Theoretical Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, PL-02-093 Warsaw, Poland
| | - Christoph E Düllmann
- Department of Chemistry-TRIGA Site, Johannes Gutenberg University, Fritz-Strassmann-Weg 2, 55128 Mainz, Germany
- GSI Helmholtzzentrum für Schwerionenforschung, Planckstr. 1, 64291 Darmstadt, Germany
- Helmholtz Institute Mainz, Staudingerweg 18, 55128 Mainz, Germany
| | - Ephraim Eliav
- School of Chemistry, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel
| | - Jonathan Engel
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, NC 27599-3255, United States of America
| | - Mingyu Fan
- Department of Physics, University of California, Santa Barbara, CA 93106, United States of America
| | | | - Kieran T Flanagan
- Photon Science Institute, Department of Physics and Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Alyssa N Gaiser
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, United States of America
| | - Ronald F Garcia Ruiz
- Massachusetts Institute of Technology, Cambridge, MA 02139, United States of America
| | - Konstantin Gaul
- Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany
| | - Thomas F Giesen
- Institute of Physics, University of Kassel, Heinrich-Plett-Str. 40, 34132 Kassel, Germany
| | - Jacinda S M Ginges
- School of Mathematics and Physics, The University of Queensland, Brisbane QLD 4072, Australia
| | | | - Gerald Gwinner
- Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T 3M9, Canada
| | | | - Steven Hoekstra
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Amsterdam, The Netherlands
| | - Jason D Holt
- TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3, Canada
- Department of Physics, McGill University, Montreal, QC H3A 2T8, Canada
| | - Nicholas R Hutzler
- California Institute of Technology, Pasadena, CA 91125, United States of America
| | - Andrew Jayich
- Department of Physics, University of California, Santa Barbara, CA 93106, United States of America
| | - Jonas Karthein
- Massachusetts Institute of Technology, Cambridge, MA 02139, United States of America
| | - Kyle G Leach
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, United States of America
- Colorado School of Mines, Golden, CO 80401, United States of America
| | - Kirk W Madison
- Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T1Z1, Canada
| | - Stephan Malbrunot-Ettenauer
- TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3, Canada
- Department of Physics, University of Toronto, 60 St. George St., Toronto, Ontario, Canada
| | | | - Iain D Moore
- Accelerator Laboratory, Department of Physics, University of Jyväskylä, Jyväskylä 40014, Finland
| | - Scott Moroch
- Massachusetts Institute of Technology, Cambridge, MA 02139, United States of America
| | - Petr Navratil
- TRIUMF, 4004 Wesbrook Mall, Vancouver, BC V6T 2A3, Canada
| | - Witold Nazarewicz
- Facility for Rare Isotope Beams and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, United States of America
| | - Gerda Neyens
- KU Leuven, Department of Physics and Astronomy, Instituut voor Kern- en Stralingsfysica, B-3001 Leuven, Belgium
| | - Eric B Norrgard
- Sensor Science Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, United States of America
| | - Nicholas Nusgart
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, United States of America
| | - Lukáš F Pašteka
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Groningen, The Netherlands
- Department of Physical and Theoretical Chemistry, Faculty of Natural Sciences, Comenius University, Bratislava, Slovakia
| | - Alexander N Petrov
- Petersburg Nuclear Physics Institute named by B.P. Konstantinov of National Research Center 'Kurchatov Institute' (NRC 'Kurchatov Institute'-PNPI), 1 Orlova roscha mcr., Gatchina 188300, Leningrad Region, Russia
- Saint Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg 199034, Russia
| | - Wolfgang R Plaß
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- II. Physikalisches Institut, Justus-Liebig-Universität Gießen, 35392 Gießen, Germany
| | - Roy A Ready
- Department of Physics, University of California, Santa Barbara, CA 93106, United States of America
| | - Moritz Pascal Reiter
- School of Physics & Astronomy, The University of Edinburgh, Peter Guthrie Tait Road, EH9 3FD Edinburgh, United Kingdom
| | - Mikael Reponen
- Accelerator Laboratory, Department of Physics, University of Jyväskylä, Jyväskylä 40014, Finland
| | | | - Marianna S Safronova
- Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, United States of America
- Joint Quantum Institute, National Institute of Standards and Technology and the University of Maryland, Gaithersburg, MD 20742, United States of America
| | - Christoph Scheidenerger
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
- II. Physikalisches Institut, Justus-Liebig-Universität Gießen, 35392 Gießen, Germany
- Helmholtz Forschungsakademie Hessen für FAIR (HFHF), Campus Gießen, Gießen, Germany
| | - Andrea Shindler
- Facility for Rare Isotope Beams & Physics Department, Michigan State University, East Lansing, MI 48824, United States of America
| | - Jaideep T Singh
- Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI, United States of America
| | - Leonid V Skripnikov
- Petersburg Nuclear Physics Institute named by B.P. Konstantinov of National Research Center 'Kurchatov Institute' (NRC 'Kurchatov Institute'-PNPI), 1 Orlova roscha mcr., Gatchina 188300, Leningrad Region, Russia
- Saint Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg 199034, Russia
| | - Anatoly V Titov
- Petersburg Nuclear Physics Institute named by B.P. Konstantinov of National Research Center 'Kurchatov Institute' (NRC 'Kurchatov Institute'-PNPI), 1 Orlova roscha mcr., Gatchina 188300, Leningrad Region, Russia
- Saint Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg 199034, Russia
| | - Silviu-Marian Udrescu
- Massachusetts Institute of Technology, Cambridge, MA 02139, United States of America
| | - Shane G Wilkins
- Massachusetts Institute of Technology, Cambridge, MA 02139, United States of America
| | - Xiaofei Yang
- School of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871, People's Republic of China
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6
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Buren B, Zhang J, Li Y. Quantum Dynamics Studies of the Li + Na 2 ( V = 0, j = 0) → Na + NaLi Reaction on a New Neural Network Potential Energy Surface. J Phys Chem A 2024; 128:5115-5127. [PMID: 38889710 DOI: 10.1021/acs.jpca.4c01891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
The ultracold reaction offers a unique opportunity to elucidate the intricate microscopic mechanism of chemical reactions, and the Na2Li system serves as a pivotal reaction system in the investigation of ultracold reactions. In this work, a high-precision potential energy surface (PES) of the Na2Li system is constructed based on high-level ab initio energy points and the neural network (NN) method, and a proper asymptotic functional form is adopted for the long-range interaction, which is suitable for the study of cold or ultracold collisions. Based on the new NN PES, the dynamics of the Li + Na2 (v = 0, j = 0) → Na + NaLi reaction are studied in the collision energy range of 10-7 to 80 cm-1. In the high collision energy range of 8 to 80 cm-1, the dynamics of the reaction is studied using the time-dependent wave packet method and the statistical quantum mechanical (SQM) method. Comparing the results of the two methods, it is found that the SQM method provides a rough description of the product ro-vibrational state distribution but overestimates the integral cross-section values. With the decrease of collision energy, the reaction differential cross section gradually changes from forward-backward symmetric scattering to predominant forward scattering. In the low collision energy range from 10-7 to 8 cm-1, the SQM method is used to study the reaction dynamics, and the rate constant in the Wigner threshold region is estimated to be 2.87 × 10-10 cm3/s.
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Affiliation(s)
- Bayaer Buren
- School of Science, Shenyang University of Technology, Shenyang 110870, China
| | - Jiapeng Zhang
- Department of Physics, Liaoning University, Shenyang 110036, China
| | - Yongqing Li
- Department of Physics, Liaoning University, Shenyang 110036, China
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7
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Mandal B, Croft JFE, Jambrina PG, Guo H, Aoiz FJ, Balakrishnan N. Stereodynamical control of cold HD + D 2 collisions. Phys Chem Chem Phys 2024; 26:18368-18381. [PMID: 38912616 DOI: 10.1039/d4cp01737d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/25/2024]
Abstract
We report full-dimensional quantum calculations of stereodynamic control of HD(v = 1, j = 2) + D2 collisions that has been probed experimentally by Perreault et al. using the Stark-induced adiabatic Raman passage (SARP) technique. Computations were performed on two highly accurate full-dimensional H4 potential energy surfaces. It is found that for both potential surfaces, rotational quenching of HD from with concurrent rotational excitation of D2 from is the dominant transition with cross sections four times larger than that of elastically scattered D2 for the same quenching transition in HD. This process was not considered in the original analysis of the SARP experiments that probed ΔjHD = -2 transitions in HD(vHD = 1, jHD = 2) + D2 collisions. Cross sections are characterized by an l = 3 resonance for ortho-D2(jD2 = 0) collisions, while both l = 1 and l = 3 resonances are observed for the para-D2(jD2 = 1) partner. While our results are in excellent agreement with prior measurements of elastic and inelastic differential cross sections, the agreement is less satisfactory with the SARP experiments, in particular for the transition for which the theoretical calculations indicate that D2 rotational excitation channel is the dominant inelastic process.
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Affiliation(s)
- Bikramaditya Mandal
- Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, Nevada 89154, USA.
| | - James F E Croft
- Department of Chemistry, Durham University, South Road, Durham, DH1 3LE, UK
| | - Pablo G Jambrina
- Departamento de Química Física, University of Salamanca, Salamanca 37008, Spain
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - F Javier Aoiz
- Departamento de Química Física, Universidad Complutense, Madrid 28040, Spain
| | - Naduvalath Balakrishnan
- Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, Nevada 89154, USA.
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8
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Chomaz L. Ultracold molecules that interact from afar form elusive quantum state. Nature 2024; 631:283-284. [PMID: 38982236 DOI: 10.1038/d41586-024-02134-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/11/2024]
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9
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He C, Nie X, Avalos V, Botsi S, Kumar S, Yang A, Dieckmann K. Efficient Creation of Ultracold Ground State ^{6}Li^{40}K Polar Molecules. PHYSICAL REVIEW LETTERS 2024; 132:243401. [PMID: 38949353 DOI: 10.1103/physrevlett.132.243401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 01/26/2024] [Accepted: 05/09/2024] [Indexed: 07/02/2024]
Abstract
We report the creation of ultracold ground state ^{6}Li^{40}K polar molecules with high efficiency. Starting from weakly bound molecules, stimulated Raman adiabatic passage is adopted to coherently transfer the molecules to their singlet rovibrational ground state |X^{1}Σ^{+},v=0,J=0⟩. By employing a singlet stimulated Raman adiabatic passage pathway and low-phase-noise narrow-linewidth lasers, we observed a one-way transfer efficiency of 96(4)%. Held in an optical dipole trap, the lifetime of the ground state molecules is measured to be 5.0(3) ms. The large permanent dipole moment of LiK is confirmed by applying a dc electric field on the molecules and performing Stark shift spectroscopy of the ground state. With recent advances in the quantum control of collisions, our work paves the way for exploring quantum many-body physics with strongly interacting ^{6}Li^{40}K molecules.
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10
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Li SJ, Holland CM, Lu Y, Cheuk LW. Blue-Detuned Magneto-optical Trap of CaF Molecules. PHYSICAL REVIEW LETTERS 2024; 132:233402. [PMID: 38905654 DOI: 10.1103/physrevlett.132.233402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 05/14/2024] [Indexed: 06/23/2024]
Abstract
A key method to produce trapped and laser-cooled molecules is the magneto-optical trap (MOT), which is conventionally created using light red detuned from an optical transition. In this work, we report a MOT for CaF molecules created using blue-detuned light. The blue-detuned MOT (BDM) achieves temperatures well below the Doppler limit and provides the highest densities and phase-space densities reported to date in CaF MOTs. Our results suggest that BDMs are likely achievable in many relatively light molecules including polyatomic ones, but our measurements suggest that BDMs will be challenging to realize in substantially heavier molecules due to sub-mK trap depths. In addition to record temperatures and densities, we find that the BDM substantially simplifies and enhances the loading of molecules into optical tweezer arrays, which are a promising platform for quantum simulation and quantum information processing. Notably, the BDM reduces molecular number requirements ninefold compared to a conventional red-detuned MOT, while not requiring additional hardware. Our work therefore substantially simplifies preparing large-scale molecular tweezer arrays, which are a novel platform for simulation of quantum many-body dynamics and quantum information processing with molecular qubits.
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11
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Khvorost T, Wójcik P, Chang C, Calvillo M, Dickerson C, Lao G, Hudson ER, Krylov AI, Alexandrova AN. Dual Optical Cycling Centers Mounted on an Organic Scaffold: New Insights from Quantum Chemistry Calculations and Symmetry Analysis. J Phys Chem Lett 2024; 15:5665-5673. [PMID: 38767654 DOI: 10.1021/acs.jpclett.4c00623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Molecules cooled to ultracold temperatures are desirable for applications in fundamental physics and quantum information science. However, cooling polyatomic molecules with more than six atoms has not yet been achieved. Building on the idea of an optical cycling center (OCC), a moiety supporting a set of localized and isolated electronic states within a polyatomic molecule, molecules with two OCCs (bi-OCCs) may afford better cooling efficiency by doubling the photon scattering rate. By using quantum chemistry calculations, we assess the extent of the coupling of the two OCCs with each other and the molecular scaffold. We show that promising coolable bi-OCC molecules can be proposed by following chemical design principles.
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Affiliation(s)
- Taras Khvorost
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Paweł Wójcik
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Cecilia Chang
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Mia Calvillo
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Claire Dickerson
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Guanming Lao
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, United States
| | - Eric R Hudson
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, United States
- Center for Quantum Science and Engineering, University of California, Los Angeles, California 90095, United States
- Challenge Institute for Quantum Computation, University of California, Los Angeles, California 90095, United States
| | - Anna I Krylov
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Anastassia N Alexandrova
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
- Center for Quantum Science and Engineering, University of California, Los Angeles, California 90095, United States
- Challenge Institute for Quantum Computation, University of California, Los Angeles, California 90095, United States
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12
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Ye J, Zoller P. Essay: Quantum Sensing with Atomic, Molecular, and Optical Platforms for Fundamental Physics. PHYSICAL REVIEW LETTERS 2024; 132:190001. [PMID: 38804927 DOI: 10.1103/physrevlett.132.190001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Indexed: 05/29/2024]
Abstract
Atomic, molecular, and optical (AMO) physics has been at the forefront of the development of quantum science while laying the foundation for modern technology. With the growing capabilities of quantum control of many atoms for engineered many-body states and quantum entanglement, a key question emerges: what critical impact will the second quantum revolution with ubiquitous applications of entanglement bring to bear on fundamental physics? In this Essay, we argue that a compelling long-term vision for fundamental physics and novel applications is to harness the rapid development of quantum information science to define and advance the frontiers of measurement physics, with strong potential for fundamental discoveries. As quantum technologies, such as fault-tolerant quantum computing and entangled quantum sensor networks, become much more advanced than today's realization, we wonder what doors of basic science can these tools unlock. We anticipate that some of the most intriguing and challenging problems, such as quantum aspects of gravity, fundamental symmetries, or new physics beyond the minimal standard model, will be tackled at the emerging quantum measurement frontier. Part of a series of Essays which concisely present author visions for the future of their field.
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Affiliation(s)
- Jun Ye
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| | - Peter Zoller
- Institute for Theoretical Physics, University of Innsbruck, 6020 Innsbruck, Austria and Institute for Quantum Optics and Quantum Information, Austrian Academy of Sciences, 6020 Innsbruck, Austria
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13
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Balakrishnan N, Jambrina PG, Croft JFE, Guo H, Aoiz FJ. Quantum stereodynamics of cold molecular collisions. Chem Commun (Camb) 2024; 60:1239-1256. [PMID: 38197484 DOI: 10.1039/d3cc04762h] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
Advances in quantum state preparations combined with molecular cooling and trapping technologies have enabled unprecedented control of molecular collision dynamics. This progress, achieved over the last two decades, has dramatically improved our understanding of molecular phenomena in the extreme quantum regime characterized by translational temperatures well below a kelvin. In this regime, collision outcomes are dominated by isolated partial waves, quantum threshold and quantum statistics effects, tiny energy splitting at the spin and hyperfine levels, and long-range forces. Collision outcomes are influenced not only by the quantum state preparation of the initial molecular states but also by the polarization of their rotational angular momentum, i.e., stereodynamics of molecular collisions. The Stark-induced adiabatic Raman passage technique developed in the last several years has become a versatile tool to study the stereodynamics of light molecular collisions in which alignment of the molecular bond axis relative to initial collision velocity can be fully controlled. Landmark experiments reported by Zare and coworkers have motivated new theoretical developments, including formalisms to describe four-vector correlations in molecular collisions that are revealed by the experiments. In this Feature article, we provide an overview of recent theoretical developments for the description of stereodynamics of cold molecular collisions and their implications to cold controlled chemistry.
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Affiliation(s)
- Naduvalath Balakrishnan
- Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, Nevada 89154, USA.
| | - Pablo G Jambrina
- Departamento de Química Física, Universidad de Salamanca, Salamanca 37008, Spain
| | - James F E Croft
- The Dodd Walls Centre for Photonic and Quantum Technologies, New Zealand and Department of Physics, University of Otago, Dunedin, New Zealand
| | - Hua Guo
- Department of Chemistry and Chemical Biology, Center for Computational Chemistry, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - F Javier Aoiz
- Departamento de Química Física, Universidad Complutense, Madrid 28040, Spain
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14
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Sidler D, Ruggenthaler M, Rubio A. Numerically Exact Solution for a Real Polaritonic System under Vibrational Strong Coupling in Thermodynamic Equilibrium: Loss of Light-Matter Entanglement and Enhanced Fluctuations. J Chem Theory Comput 2023; 19:8801-8814. [PMID: 37972347 PMCID: PMC10720342 DOI: 10.1021/acs.jctc.3c00092] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 10/25/2023] [Accepted: 10/25/2023] [Indexed: 11/19/2023]
Abstract
The first numerically exact simulation of a full ab initio molecular quantum system (HD+) under strong ro-vibrational coupling to a quantized optical cavity mode in thermal equilibrium is presented. Theoretical challenges in describing strongly coupled systems of mixed quantum statistics (bosons and Fermions) are discussed and circumvented by the specific choice of our molecular system. Our numerically exact simulations highlight the absence of zero temperature for the strongly coupled matter and light subsystems, due to cavity-induced noncanonical conditions. Furthermore, we explore the temperature dependency of light-matter quantum entanglement, which emerges for the ground state but is quickly lost already in the deep cryogenic regime. This is in contrast to predictions from the Jaynes-Cummings model, which is the standard starting point to model collective strong-coupling chemistry phenomenologically. Moreover, we find that the fluctuations of matter remain modified by the quantum nature of the thermal and vacuum-field fluctuations for significant temperatures, e.g., at ambient conditions. These observations (loss of entanglement and coupling to quantum fluctuations) have implications for the understanding and control of polaritonic chemistry and materials science, since a semiclassical theoretical description of light-matter interaction becomes reasonable, but the typical (classical) canonical equilibrium assumption for the nuclear subsystem remains violated. This opens the door for quantum fluctuation-induced stochastic resonance phenomena under vibrational strong coupling, which have been suggested as a plausible theoretical mechanism to explain the experimentally observed resonance phenomena in the absence of periodic driving that has not yet been fully understood.
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Affiliation(s)
- Dominik Sidler
- Max
Planck Institute for the Structure and Dynamics of Matter and Center
for Free-Electron Laser Science, Luruper Chaussee 149, Hamburg 22761, Germany
- The
Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Michael Ruggenthaler
- Max
Planck Institute for the Structure and Dynamics of Matter and Center
for Free-Electron Laser Science, Luruper Chaussee 149, Hamburg 22761, Germany
- The
Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Angel Rubio
- Max
Planck Institute for the Structure and Dynamics of Matter and Center
for Free-Electron Laser Science, Luruper Chaussee 149, Hamburg 22761, Germany
- The
Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, Hamburg 22761, Germany
- Center
for Computational Quantum Physics, Flatiron Institute, 162 Fifth Avenue, New York, New York 10010, United States
- Nano-Bio
Spectroscopy Group, University of the Basque Country (UPV/EHU), San Sebastián 20018, Spain
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15
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Muleady SR, Yang M, White SR, Rey AM. Validating Phase-Space Methods with Tensor Networks in Two-Dimensional Spin Models with Power-Law Interactions. PHYSICAL REVIEW LETTERS 2023; 131:150401. [PMID: 37897760 DOI: 10.1103/physrevlett.131.150401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 09/07/2023] [Indexed: 10/30/2023]
Abstract
Using a recently developed extension of the time-dependent variational principle for matrix product states, we evaluate the dynamics of 2D power-law interacting XXZ models, implementable in a variety of state-of-the-art experimental platforms. We compute the spin squeezing as a measure of correlations in the system, and compare to semiclassical phase-space calculations utilizing the discrete truncated Wigner approximation (DTWA). We find the latter efficiently and accurately captures the scaling of entanglement with system size in these systems, despite the comparatively resource-intensive tensor network representation of the dynamics. We also compare the steady-state behavior of DTWA to thermal ensemble calculations with tensor networks. Our results open a way to benchmark dynamical calculations for two-dimensional quantum systems, and allow us to rigorously validate recent predictions for the generation of scalable entangled resources for metrology in these systems.
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Affiliation(s)
- Sean R Muleady
- JILA, National Institute of Standards and Technology and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
- Center for Theory of Quantum Matter, University of Colorado, Boulder, Colorado 80309, USA
| | - Mingru Yang
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
- University of Vienna, Faculty of Physics, Boltzmanngasse 5, 1090 Wien, Austria
| | - Steven R White
- Department of Physics and Astronomy, University of California, Irvine, California 92697, USA
| | - Ana Maria Rey
- JILA, National Institute of Standards and Technology and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
- Center for Theory of Quantum Matter, University of Colorado, Boulder, Colorado 80309, USA
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16
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Bigagli N, Savin DW, Will S. Laser Scheme for Doppler Cooling of the Hydroxyl Cation (OH +). J Phys Chem A 2023; 127:8194-8199. [PMID: 37738380 DOI: 10.1021/acs.jpca.3c03248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/24/2023]
Abstract
We report on a cycling scheme for Doppler cooling of trapped OH+ ions using transitions between the electronic ground state X3Σ- and the first excited triplet state A3Π. We have identified relevant transitions for photon cycling and repumping, have found that coupling into other electronic states is strongly suppressed, and have calculated the number of photon scatterings required to cool OH+ to a temperature where Raman sideband cooling can take over. In contrast to the standard approach, where molecular ions are sympathetically cooled, our scheme does not require co-trapping of another species and opens the door to the creation of pure samples of cold molecular ions with potential applications in quantum information, quantum chemistry, and astrochemistry. The laser cooling scheme identified for OH+ is efficient despite the absence of near-diagonal Franck-Condon factors, suggesting that broader classes of molecules and molecular ions are amenable to laser cooling than commonly assumed.
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Affiliation(s)
- Niccolò Bigagli
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Daniel W Savin
- Columbia Astrophysics Laboratory, Columbia University, New York, New York 10027, United States
| | - Sebastian Will
- Department of Physics, Columbia University, New York, New York 10027, United States
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17
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Song H, Guo H. Theoretical Insights into the Dynamics of Gas-Phase Bimolecular Reactions with Submerged Barriers. ACS PHYSICAL CHEMISTRY AU 2023; 3:406-418. [PMID: 37780541 PMCID: PMC10540288 DOI: 10.1021/acsphyschemau.3c00009] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 06/02/2023] [Accepted: 06/06/2023] [Indexed: 10/03/2023]
Abstract
Much attention has been paid to the dynamics of both activated gas-phase bimolecular reactions, which feature monotonically increasing integral cross sections and Arrhenius kinetics, and their barrierless capture counterparts, which manifest monotonically decreasing integral cross sections and negative temperature dependence of the rate coefficients. In this Perspective, we focus on the dynamics of gas-phase bimolecular reactions with submerged barriers, which often involve radicals or ions and are prevalent in combustion, atmospheric chemistry, astrochemistry, and plasma chemistry. The temperature dependence of the rate coefficients for such reactions is often non-Arrhenius and complex, and the corresponding dynamics may also be quite different from those with significant barriers or those completely dominated by capture. Recent experimental and theoretical studies of such reactions, particularly at relatively low temperatures or collision energies, have revealed interesting dynamical behaviors, which are discussed here. The new knowledge enriches our understanding of the dynamics of these unusual reactions.
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Affiliation(s)
- Hongwei Song
- State
Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science
and Technology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Hua Guo
- Department
of Chemistry and Chemical Biology, University
of New Mexico, Albuquerque, New Mexico 87131, United States
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18
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Franke J, Muleady SR, Kaubruegger R, Kranzl F, Blatt R, Rey AM, Joshi MK, Roos CF. Quantum-enhanced sensing on optical transitions through finite-range interactions. Nature 2023; 621:740-745. [PMID: 37648868 DOI: 10.1038/s41586-023-06472-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 07/21/2023] [Indexed: 09/01/2023]
Abstract
The control over quantum states in atomic systems has led to the most precise optical atomic clocks so far1-3. Their sensitivity is bounded at present by the standard quantum limit, a fundamental floor set by quantum mechanics for uncorrelated particles, which can-nevertheless-be overcome when operated with entangled particles. Yet demonstrating a quantum advantage in real-world sensors is extremely challenging. Here we illustrate a pathway for harnessing large-scale entanglement in an optical transition using 1D chains of up to 51 ions with interactions that decay as a power-law function of the ion separation. We show that our sensor can emulate many features of the one-axis-twisting (OAT) model, an iconic, fully connected model known to generate scalable squeezing4 and Greenberger-Horne-Zeilinger-like states5-8. The collective nature of the state manifests itself in the preservation of the total transverse magnetization, the reduced growth of the structure factor, that is, spin-wave excitations (SWE), at finite momenta, the generation of spin squeezing comparable with OAT (a Wineland parameter9,10 of -3.9 ± 0.3 dB for only N = 12 ions) and the development of non-Gaussian states in the form of multi-headed cat states in the Q-distribution. We demonstrate the metrological utility of the states in a Ramsey-type interferometer, in which we reduce the measurement uncertainty by -3.2 ± 0.5 dB below the standard quantum limit for N = 51 ions.
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Affiliation(s)
- Johannes Franke
- Institut für Experimentalphysik, Universität Innsbruck, Innsbruck, Austria
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, Innsbruck, Austria
| | - Sean R Muleady
- JILA, NIST and Department of Physics, University of Colorado, Boulder, CO, USA
- Center for Theory of Quantum Matter, University of Colorado, Boulder, CO, USA
| | - Raphael Kaubruegger
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, Innsbruck, Austria
- Institut für Theoretische Physik, Universität Innsbruck, Innsbruck, Austria
| | - Florian Kranzl
- Institut für Experimentalphysik, Universität Innsbruck, Innsbruck, Austria
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, Innsbruck, Austria
| | - Rainer Blatt
- Institut für Experimentalphysik, Universität Innsbruck, Innsbruck, Austria
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, Innsbruck, Austria
| | - Ana Maria Rey
- JILA, NIST and Department of Physics, University of Colorado, Boulder, CO, USA.
- Center for Theory of Quantum Matter, University of Colorado, Boulder, CO, USA.
| | - Manoj K Joshi
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, Innsbruck, Austria
| | - Christian F Roos
- Institut für Experimentalphysik, Universität Innsbruck, Innsbruck, Austria.
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, Innsbruck, Austria.
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19
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Perera CA, Amarasinghe C, Guo H, Suits AG. Cold collisions of hot molecules. Phys Chem Chem Phys 2023; 25:22595-22606. [PMID: 37602475 DOI: 10.1039/d3cp02071a] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/22/2023]
Abstract
In this Perspective, we review our recent work on rotationally inelastic collisions of highly vibrationally excited NO molecules prepared in single rotational and parity levels at v = 10 using stimulated emission pumping (SEP). This state preparation is employed in a recently developed crossed molecular beam apparatus where two nearly copropagating molecular beams achieve an intersection angle of 4° at the interaction region. This near-copropagating beam geometry of the molecular beams permits very wide tuning of the collision energy, from far above room temperature down to 2 K where we test the theoretical treatment of the attractive part of the potentials and the difference potential for the first time. We have obtained differential cross sections for state-to-state collisions of NO (v = 10) with Ar and Ne in both spin-orbit manifolds using velocity map imaging. Overall good agreement of the experimental results was seen with quantum mechanical close-coupling calculations done on both coupled-cluster and multi-reference configuration interaction potential energy surfaces. Probing cold collisions of NO carrying ∼2 eV of vibrational excitation allows us to test state-of-the-art theory in this extreme nonequilibrium regime.
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Affiliation(s)
- Chatura A Perera
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA.
| | | | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Arthur G Suits
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA.
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20
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Van Benschoten W, Petras HR, Shepherd JJ. Electronic Free Energy Surface of the Nitrogen Dimer Using First-Principles Finite Temperature Electronic Structure Methods. J Phys Chem A 2023; 127:6842-6856. [PMID: 37535315 PMCID: PMC10440793 DOI: 10.1021/acs.jpca.3c01741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 07/20/2023] [Indexed: 08/04/2023]
Abstract
We use full configuration interaction and density matrix quantum Monte Carlo methods to calculate the electronic free energy surface of the nitrogen dimer within the free-energy Born-Oppenheimer approximation. As the temperature is raised from T = 0, we find a temperature regime in which the internal energy causes bond strengthening. At these temperatures, adding in the entropy contributions is required to cause the bond to gradually weaken with increasing temperature. We predict a thermally driven dissociation for the nitrogen dimer between 22,000 to 63,200 K depending on symmetries and basis set. Inclusion of more spatial and spin symmetries reduces the temperature required. The origin of these observations is explored using the structure of the density matrix at various temperatures and bond lengths.
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Affiliation(s)
| | - Hayley R. Petras
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - James J. Shepherd
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
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21
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Asnaashari K, Krems RV, Tscherbul TV. General Classification of Qubit Encodings in Ultracold Diatomic Molecules. J Phys Chem A 2023; 127:6593-6602. [PMID: 37494464 DOI: 10.1021/acs.jpca.3c02835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
Owing to their rich internal structure and significant long-range interactions, ultracold molecules have been widely explored as carriers of quantum information. Several different schemes for encoding qubits into molecular states, both bare and field-dressed, have been proposed. At the same time, the rich internal structure of molecules leaves many unexplored possibilities for qubit encodings. We show that all molecular qubit encodings can be classified into four classes by the type of the effective interaction between the qubits. In the case of polar molecules, the four classes are determined by the relative magnitudes of matrix elements of the dipole moment operator in the single-molecule basis. We exemplify our classification scheme by considering the encoding of the effective spin-1/2 system into nonadjacent rotational states (e.g., N = 0 and 2) of polar and nonpolar molecules with the same nuclear spin projection. Our classification scheme is designed to inform the optimal choice of molecular qubit encoding for quantum information storage and processing applications, as well as for dynamical generation of many-body entangled states and for quantum annealing.
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Affiliation(s)
- Kasra Asnaashari
- Department of Chemistry, University of British Columbia, Vancouver V6T 1Z1, Canada
| | - Roman V Krems
- Department of Chemistry, University of British Columbia, Vancouver V6T 1Z1, Canada
| | - Timur V Tscherbul
- Department of Physics, University of Nevada, Reno, Nevada 89557, United States
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22
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Bilitewski T, Rey AM. Manipulating Growth and Propagation of Correlations in Dipolar Multilayers: From Pair Production to Bosonic Kitaev Models. PHYSICAL REVIEW LETTERS 2023; 131:053001. [PMID: 37595247 DOI: 10.1103/physrevlett.131.053001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 07/14/2023] [Indexed: 08/20/2023]
Abstract
We study the nonequilibrium dynamics of dipoles confined in multiple stacked two-dimensional layers realizing a long-range interacting quantum spin 1/2 XXX model. We demonstrate that strong in-plane interactions can protect a manifold of collective layer dynamics. This then allows us to map the many-body spin dynamics to bosonic models. In a bilayer configuration we show how to engineer the paradigmatic two-mode squeezing Hamiltonian known from quantum optics, resulting in exponential production of entangled pairs and generation of metrologically useful entanglement from initially prepared product states. In multilayer configurations we engineer a bosonic variant of the Kitaev model displaying chiral propagation along the layer direction. Our study illustrates how the control over interactions, lattice geometry, and state preparation in interacting dipolar systems uniquely afforded by AMO platforms such as Rydberg and magnetic atoms, polar molecules, or trapped ions allows for the control over the temporal and spatial propagation of correlations for applications in quantum sensing and quantum simulation.
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Affiliation(s)
- Thomas Bilitewski
- Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078, USA
| | - Ana Maria Rey
- JILA, National Institute of Standards and Technology and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
- Center for Theory of Quantum Matter, University of Colorado, Boulder, Colorado 80309, USA
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23
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Holland CM, Lu Y, Cheuk LW. Bichromatic Imaging of Single Molecules in an Optical Tweezer Array. PHYSICAL REVIEW LETTERS 2023; 131:053202. [PMID: 37595242 DOI: 10.1103/physrevlett.131.053202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 07/04/2023] [Indexed: 08/20/2023]
Abstract
We report on a novel bichromatic fluorescent imaging scheme for background-free detection of single CaF molecules trapped in an optical tweezer array. By collecting fluorescence on one optical transition while using another for laser cooling, we achieve an imaging fidelity of 97.7(2)% and a nondestructive detection fidelity of 95.5(6)%. Notably, these fidelities are achieved with a modest photon budget, suggesting that the method could be extended to more complex laser-coolable molecules with less favorable optical cycling properties. We also report on a framework and new methods to characterize various loss mechanisms that occur generally during fluorescent detection of trapped molecules, including two-photon decay and admixtures of higher excited states that are induced by the trapping light. In particular, we develop a novel method to dispersively measure transition matrix elements between electronically excited states. The method could also be used to measure arbitrarily small Franck-Condon factors between electronically excited states, which could significantly aid in ongoing efforts to laser cool complex polyatomic molecules.
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Affiliation(s)
- Connor M Holland
- Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
| | - Yukai Lu
- Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
- Department of Electrical and Computer Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - Lawrence W Cheuk
- Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
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24
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Gao XY, Blume D, Yan Y. Temperature-Dependent Contact of Weakly Interacting Single-Component Fermi Gases and Loss Rate of Degenerate Polar Molecules. PHYSICAL REVIEW LETTERS 2023; 131:043401. [PMID: 37566834 DOI: 10.1103/physrevlett.131.043401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/21/2023] [Accepted: 06/27/2023] [Indexed: 08/13/2023]
Abstract
Motivated by the experimental realization of single-component degenerate Fermi gases of polar ground state KRb molecules with intrinsic two-body losses [L. De Marco et al., A degenerate Fermi gas of polar molecules, Science 363, 853 (2019).SCIEAS0036-807510.1126/science.aau7230], this work studies the finite-temperature loss rate of single-component Fermi gases with weak interactions. First, we establish a relationship between the two-body loss rate and the p-wave contact. Second, we evaluate the contact of the homogeneous system in the low-temperature regime using p-wave Fermi liquid theory and in the high-temperature regime using the second-order virial expansion. Third, conjecturing that there are no phase transitions between the two temperature regimes, we smoothly interpolate the results to intermediate temperatures. It is found that the contact is constant at temperatures close to zero and increases first quadratically with increasing temperature and finally-in agreement with the Bethe-Wigner threshold law-linearly at high temperatures. Fourth, applying the local-density approximation, we obtain the loss-rate coefficient for the harmonically trapped system, reproducing the experimental KRb loss measurements within a unified theoretical framework over a wide temperature regime without fitting parameters. Our results for the contact are not only applicable to molecular p-wave gases but also to atomic single-component Fermi gases, such as ^{40}K and ^{6}Li.
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Affiliation(s)
- Xin-Yuan Gao
- Department of Physics, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - D Blume
- Homer L. Dodge Department of Physics and Astronomy, The University of Oklahoma, 440 W. Brooks Street, Norman, Oklahoma 73019, USA
- Center for Quantum Research and Technology, The University of Oklahoma, 440 W. Brooks Street, Norman, Oklahoma 73019, USA
| | - Yangqian Yan
- Department of Physics, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- The Chinese University of Hong Kong Shenzhen Research Institute, 518057 Shenzhen, China
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25
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Changala PB, Genossar-Dan N, Brudner E, Gur T, Baraban JH, McCarthy MC. Structural and electronic trends of optical cycling centers in polyatomic molecules revealed by microwave spectroscopy of MgCCH, CaCCH, and SrCCH. Proc Natl Acad Sci U S A 2023; 120:e2303586120. [PMID: 37399375 PMCID: PMC10334755 DOI: 10.1073/pnas.2303586120] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Accepted: 05/23/2023] [Indexed: 07/05/2023] Open
Abstract
The unique optical cycling efficiency of alkaline earth metal-ligand molecules has enabled significant advances in polyatomic laser cooling and trapping. Rotational spectroscopy is an ideal tool for probing the molecular properties that underpin optical cycling, thereby elucidating the design principles for expanding the chemical diversity and scope of these platforms for quantum science. We present a comprehensive study of the structure and electronic properties in alkaline earth metal acetylides with high-resolution microwave spectra of 17 isotopologues of MgCCH, CaCCH, and SrCCH in their 2Σ+ ground electronic states. The precise semiexperimental equilibrium geometry of each species has been derived by correcting the measured rotational constants for electronic and zero-point vibrational contributions calculated with high-level quantum chemistry methods. The well-resolved hyperfine structure associated with the 1,2H, 13C, and metal nuclear spins provides further information on the distribution and hybridization of the metal-centered, optically active unpaired electron. Together, these measurements allow us to correlate trends in chemical bonding and structure with the electronic properties that promote efficient optical cycling essential to next-generation experiments in precision measurement and quantum control of complex polyatomic molecules.
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Affiliation(s)
- P. Bryan Changala
- Atomic and Molecular Physics Division, Center for Astrophysics | Harvard & Smithsonian, Cambridge, MA02138
| | - Nadav Genossar-Dan
- Department of Chemistry, Ben-Gurion University of the Negev, Beer Sheva8410501, Israel
| | - Ella Brudner
- Department of Chemistry, Ben-Gurion University of the Negev, Beer Sheva8410501, Israel
| | - Tomer Gur
- Department of Chemistry, Ben-Gurion University of the Negev, Beer Sheva8410501, Israel
| | - Joshua H. Baraban
- Department of Chemistry, Ben-Gurion University of the Negev, Beer Sheva8410501, Israel
| | - Michael C. McCarthy
- Atomic and Molecular Physics Division, Center for Astrophysics | Harvard & Smithsonian, Cambridge, MA02138
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26
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Guttridge A, Ruttley DK, Baldock AC, González-Férez R, Sadeghpour HR, Adams CS, Cornish SL. Observation of Rydberg Blockade Due to the Charge-Dipole Interaction between an Atom and a Polar Molecule. PHYSICAL REVIEW LETTERS 2023; 131:013401. [PMID: 37478436 DOI: 10.1103/physrevlett.131.013401] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 05/15/2023] [Indexed: 07/23/2023]
Abstract
We demonstrate Rydberg blockade due to the charge-dipole interaction between a single Rb atom and a single RbCs molecule confined in optical tweezers. The molecule is formed by magnetoassociation of a Rb+Cs atom pair and subsequently transferred to the rovibrational ground state with an efficiency of 91(1)%. Species-specific tweezers are used to control the separation between the atom and molecule. The charge-dipole interaction causes blockade of the transition to the Rb(52s) Rydberg state, when the atom-molecule separation is set to 310(40) nm. The observed excitation dynamics are in good agreement with simulations using calculated interaction potentials. Our results open up the prospect of a hybrid platform where quantum information is transferred between individually trapped molecules using Rydberg atoms.
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Affiliation(s)
- Alexander Guttridge
- Department of Physics, Durham University, South Road, Durham, DH1 3LE, United Kingdom
- Joint Quantum Centre Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - Daniel K Ruttley
- Department of Physics, Durham University, South Road, Durham, DH1 3LE, United Kingdom
- Joint Quantum Centre Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - Archie C Baldock
- Department of Physics, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - Rosario González-Férez
- Instituto Carlos I de Física Teórica y Computacional, and Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, 18071 Granada, Spain
| | - H R Sadeghpour
- ITAMP, Center for Astrophysics | Harvard & Smithsonian, Cambridge, Massachusetts 02138, USA
| | - C S Adams
- Department of Physics, Durham University, South Road, Durham, DH1 3LE, United Kingdom
- Joint Quantum Centre Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - Simon L Cornish
- Department of Physics, Durham University, South Road, Durham, DH1 3LE, United Kingdom
- Joint Quantum Centre Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
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27
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Zhang C, Hutzler NR, Cheng L. Intensity-Borrowing Mechanisms Pertinent to Laser Cooling of Linear Polyatomic Molecules. J Chem Theory Comput 2023. [PMID: 37384588 DOI: 10.1021/acs.jctc.3c00408] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/01/2023]
Abstract
A study of the intensity-borrowing mechanisms important to optical cycling transitions in laser-coolable polyatomic molecules arising from non-adiabatic coupling, contributions beyond the Franck-Condon approximation, and Fermi resonances is reported. It has been shown to be necessary to include non-adiabatic coupling to obtain computational accuracy that is sufficient to be useful for laser cooling of molecules. The predicted vibronic branching ratios using perturbation theory based on the non-adiabatic mechanisms have been demonstrated to agree well with those obtained from variational discrete variable representation calculations for representative molecules including CaOH, SrOH, and YbOH. The electron-correlation and basis-set effects on the calculated transition properties, including the vibronic coupling constants, the spin-orbit coupling matrix elements, and the transition dipole moments, and on the calculated branching ratios have been thoroughly studied. The vibronic branching ratios predicted using the present methodologies demonstrate that RaOH is a promising radioactive molecule candidate for laser cooling.
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Affiliation(s)
- Chaoqun Zhang
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Nicholas R Hutzler
- Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, California 91125, United States
| | - Lan Cheng
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States
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28
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Pang R, Yin J, Wang Y, Lin Q, Wang Z, Xu L, Hou S, Wang H, Yin J, Yang T. Theoretical Investigation of Spectroscopic Properties of the Alkaline-Earth-Metal Monohydrides toward Laser Cooling and Magneto-Optical Trapping. ACS OMEGA 2023; 8:19391-19401. [PMID: 37305276 PMCID: PMC10249082 DOI: 10.1021/acsomega.3c00352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 04/10/2023] [Indexed: 06/13/2023]
Abstract
Alkaline-earth-metal monohydrides MH (M = Be, Mg, Ca, Sr, Ba) have long been regarded as promising candidates toward laser cooling and trapping; however, their rich internal level structures that are amenable to magneto-optical trapping have not been completely explored. Here, we first systematically evaluated Franck-Condon factors of these alkaline-earth-metal monohydrides in the A2Π1/2 ← X2Σ+ transition, exploiting three respective methods (the Morse potential, the closed-form approximation, and the Rydberg-Klein-Rees method). The effective Hamiltonian matrix was introduced for MgH, CaH, SrH, and BaH individually in order to figure out their molecular hyperfine structures of X2Σ+, the transition wavelengths in the vacuum, and hyperfine branching ratios of A2Π1/2(J' = 1/2,+) ← X2Σ+(N = 1,-), followed by possible sideband modulation proposals to address all hyperfine manifolds. Lastly, the Zeeman energy level structures and associated magnetic g factors of the ground state X2Σ+(N = 1,-) were also presented. Our theoretical results here not only shed more light on the molecular spectroscopy of alkaline-earth-metal monohydrides toward laser cooling and magneto-optical trapping but also can contribute to research in molecular collisions involving few-atom molecular systems, spectral analysis in astrophysics and astrochemistry, and even precision measurement of fundamental constants such as the quest for nonzero detection of electron's electric dipole moment.
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Affiliation(s)
- Renjun Pang
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, P. R. China
| | - Junhao Yin
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, P. R. China
| | - Yueyang Wang
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, P. R. China
| | - Qinning Lin
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, P. R. China
| | - Zesen Wang
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, P. R. China
| | - Liang Xu
- Shanghai
Key Laboratory of Modern Optical Systems, University of Shanghai for Science and Technology, Shanghai 200093, P. R. China
| | - Shunyong Hou
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, P. R. China
| | - Hailing Wang
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, P. R. China
| | - Jianping Yin
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, P. R. China
| | - Tao Yang
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, P. R. China
- Collaborative
Innovation Center of Extreme Optics, Shanxi
University, Taiyuan, Shanxi 030006, P.
R. China
- Xinjiang
Astronomical Observatory, Chinese Academy
of Sciences, 150 Science
1-Street, Urumqi, Xinjiang 830011, P. R. China
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29
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Ruttley DK, Guttridge A, Spence S, Bird RC, Le Sueur CR, Hutson JM, Cornish SL. Formation of Ultracold Molecules by Merging Optical Tweezers. PHYSICAL REVIEW LETTERS 2023; 130:223401. [PMID: 37327422 DOI: 10.1103/physrevlett.130.223401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/24/2023] [Accepted: 04/25/2023] [Indexed: 06/18/2023]
Abstract
We demonstrate the formation of a single RbCs molecule during the merging of two optical tweezers, one containing a single Rb atom and the other a single Cs atom. Both atoms are initially predominantly in the motional ground states of their respective tweezers. We confirm molecule formation and establish the state of the molecule formed by measuring its binding energy. We find that the probability of molecule formation can be controlled by tuning the confinement of the traps during the merging process, in good agreement with coupled-channel calculations. We show that the conversion efficiency from atoms to molecules using this technique is comparable to magnetoassociation.
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Affiliation(s)
- Daniel K Ruttley
- Department of Physics and Joint Quantum Centre (JQC) Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - Alexander Guttridge
- Department of Physics and Joint Quantum Centre (JQC) Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - Stefan Spence
- Department of Physics and Joint Quantum Centre (JQC) Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - Robert C Bird
- Department of Chemistry and Joint Quantum Centre (JQC) Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - C Ruth Le Sueur
- Department of Chemistry and Joint Quantum Centre (JQC) Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - Jeremy M Hutson
- Department of Chemistry and Joint Quantum Centre (JQC) Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
| | - Simon L Cornish
- Department of Physics and Joint Quantum Centre (JQC) Durham-Newcastle, Durham University, South Road, Durham, DH1 3LE, United Kingdom
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30
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Szczepkowski J, Gronowski M, Grochola A, Jastrzebski W, Tomza M, Kowalczyk P. Excited Electronic States of Sr 2: Ab Initio Predictions and Experimental Observation of the 2 1Σ u+ State. J Phys Chem A 2023; 127:4473-4482. [PMID: 37192534 DOI: 10.1021/acs.jpca.3c02056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Despite its apparently simple nature with four valence electrons, the strontium dimer constitutes a challenge for modern electronic structure theory. Here we focus on excited electronic states of Sr2, which we investigate theoretically up to 25000 cm-1 above the ground state, to guide and explain new spectroscopic measurements. In particular, we focus on potential energy curves for the 11Σu+, 21Σu+, 11Πu, 21Πu, and 11Δu states computed using several variants of ab initio coupled-cluster and configuration-interaction methods to benchmark them. In addition, a new experimental study of the excited 21Σu+ state using polarization labeling spectroscopy is presented, which extends knowledge of this state to high vibrational levels, where perturbation by higher electronic states is observed. The available experimental observations are compared with the theoretical predictions and help to assess the accuracy and limitations of employed theoretical models. The present results pave the way for future more accurate theoretical and experimental spectroscopic studies.
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Affiliation(s)
- Jacek Szczepkowski
- Institute of Physics, Polish Academy of Sciences, al. Lotników 32/46, 02-668 Warsaw, Poland
| | - Marcin Gronowski
- Institute of Theoretical Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093 Warszawa, Poland
| | - Anna Grochola
- Institute of Physics, Polish Academy of Sciences, al. Lotników 32/46, 02-668 Warsaw, Poland
| | | | - Michał Tomza
- Institute of Theoretical Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093 Warszawa, Poland
| | - Paweł Kowalczyk
- Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Pasteura 5, 02-093 Warszawa, Poland
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31
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Hollerith S, Zeiher J. Rydberg Macrodimers: Diatomic Molecules on the Micrometer Scale. J Phys Chem A 2023; 127:3925-3939. [PMID: 36977279 PMCID: PMC10184126 DOI: 10.1021/acs.jpca.2c08454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 03/17/2023] [Indexed: 03/30/2023]
Abstract
Controlling molecular binding at the level of single atoms is one of the holy grails of quantum chemistry. Rydberg macrodimers─bound states between highly excited Rydberg atoms─provide a novel perspective in this direction. Resulting from binding potentials formed by the strong, long-range interactions of Rydberg states, Rydberg macrodimers feature bond lengths in the micrometer regime, exceeding those of conventional molecules by orders of magnitude. Using single-atom control in quantum gas microscopes, the unique properties of these exotic states can be studied with unprecedented control, including the response to magnetic fields or the polarization of light in their photoassociation. The high accuracy achieved in spectroscopic studies of macrodimers makes them an ideal testbed to benchmark Rydberg interactions, with direct relevance to quantum computing and information protocols where these are employed. This review provides a historic overview and summarizes the recent findings in the field of Rydberg macrodimers. Furthermore, it presents new data on interactions between macrodimers, leading to a phenomenon analogous to Rydberg blockade at the level of molecules, opening the path toward studying many-body systems of ultralong-range Rydberg molecules.
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Affiliation(s)
- Simon Hollerith
- Max-Planck-Institut
für Quantenoptik, 85748 Garching, Germany
| | - Johannes Zeiher
- Max-Planck-Institut
für Quantenoptik, 85748 Garching, Germany
- Munich
Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
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32
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Zeng Y, Hutzler NR. Nonresonant cavity for multipass laser intensity buildup. APPLIED OPTICS 2023; 62:3574-3580. [PMID: 37706972 DOI: 10.1364/ao.487531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 04/09/2023] [Indexed: 09/15/2023]
Abstract
A nonresonant cavity to build up laser intensity is modeled, developed, and tested. It can be used for overlapping multiple lasers of different wavelengths, increasing their intensities by more than an order of magnitude while maintaining good uniformity. It is simple to set up, has flexible optical characteristics, and is robust against perturbations. The intensity buildup requires no resonances, and the wavelength dependence of the performance is limited only by the mirror coatings. The cavity can be used, for example, in applications requiring a spatially constrained intensity buildup, such as in atomic and molecular traps.
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33
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Hallas C, Vilas NB, Anderegg L, Robichaud P, Winnicki A, Zhang C, Cheng L, Doyle JM. Optical Trapping of a Polyatomic Molecule in an ℓ-Type Parity Doublet State. PHYSICAL REVIEW LETTERS 2023; 130:153202. [PMID: 37115898 DOI: 10.1103/physrevlett.130.153202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 02/13/2023] [Indexed: 06/19/2023]
Abstract
We report optical trapping of a polyatomic molecule, calcium monohydroxide (CaOH). CaOH molecules from a magneto-optical trap are sub-Doppler laser cooled to 20(3) μK in free space and loaded into an optical dipole trap. We attain an in-trap molecule number density of 3(1)×10^{9} cm^{-3} at a temperature of 57(8) μK. Trapped CaOH molecules are optically pumped into an excited vibrational bending mode, whose ℓ-type parity doublet structure is a potential resource for a wide range of proposed quantum science applications with polyatomic molecules. We measure the spontaneous, radiative lifetime of this bending mode state to be ∼0.7 s.
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Affiliation(s)
- Christian Hallas
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, USA
| | - Nathaniel B Vilas
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, USA
| | - Loïc Anderegg
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, USA
| | - Paige Robichaud
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, USA
| | - Andrew Winnicki
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, USA
| | - Chaoqun Zhang
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Lan Cheng
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - John M Doyle
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA
- Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, USA
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34
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Morita M, Kendrick BK, Kłos J, Kotochigova S, Brumer P, Tscherbul TV. Signatures of Non-universal Quantum Dynamics of Ultracold Chemical Reactions of Polar Alkali Dimer Molecules with Alkali Metal Atoms: Li( 2S) + NaLi( a3Σ +) → Na( 2S) + Li 2( a3Σ u+). J Phys Chem Lett 2023; 14:3413-3421. [PMID: 37001115 DOI: 10.1021/acs.jpclett.3c00159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Ultracold chemical reactions of weakly bound triplet-state alkali metal dimer molecules have recently attracted much experimental interest. We perform rigorous quantum scattering calculations with a new ab initio potential energy surface to explore the chemical reaction of spin-polarized NaLi(a3Σ+) and Li(2S) to form Li2(a3Σu+) and Na(2S). The reaction is exothermic and proceeds readily at ultralow temperatures. Significantly, we observe strong sensitivity of the total reaction rate to small variations of the three-body part of the Li2Na interaction at short range, which we attribute to a relatively small number of open Li2(a3Σu+) product channels populated in the reaction. This provides the first signature of highly non-universal dynamics seen in rigorous quantum reactive scattering calculations of an ultracold exothermic insertion reaction involving a polar alkali dimer molecule, opening up the possibility of probing microscopic interactions in atom+molecule collision complexes via ultracold reactive scattering experiments.
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Affiliation(s)
- Masato Morita
- Chemical Physics Theory Group, Department of Chemistry, and Center for Quantum Information and Quantum Control, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Brian K Kendrick
- Theoretical Division (T-1, MS B221), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Jacek Kłos
- Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, United States
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Svetlana Kotochigova
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Paul Brumer
- Chemical Physics Theory Group, Department of Chemistry, and Center for Quantum Information and Quantum Control, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Timur V Tscherbul
- Department of Physics, University of Nevada, Reno, Nevada 89557, United States
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35
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Tscherbul TV, Ye J, Rey AM. Robust Nuclear Spin Entanglement via Dipolar Interactions in Polar Molecules. PHYSICAL REVIEW LETTERS 2023; 130:143002. [PMID: 37084438 DOI: 10.1103/physrevlett.130.143002] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 03/13/2023] [Indexed: 05/03/2023]
Abstract
We propose a general protocol for on-demand generation of robust entangled states of nuclear and/or electron spins of ultracold ^{1}Σ and ^{2}Σ polar molecules using electric dipolar interactions. By encoding a spin-1/2 degree of freedom in a combined set of spin and rotational molecular levels, we theoretically demonstrate the emergence of effective spin-spin interactions of the Ising and XXZ forms, enabled by efficient magnetic control over electric dipolar interactions. We show how to use these interactions to create long-lived cluster and squeezed spin states.
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Affiliation(s)
- Timur V Tscherbul
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - Jun Ye
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
| | - Ana Maria Rey
- JILA, National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA
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36
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Yang Z, Chen H, Buren B, Chen M. Globally Accurate Gaussian Process Potential Energy Surface and Quantum Dynamics Studies on the Li( 2S) + Na 2 → LiNa + Na Reaction at Low Collision Energies. Molecules 2023; 28:2938. [PMID: 37049701 PMCID: PMC10096016 DOI: 10.3390/molecules28072938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 03/22/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
The LiNa2 reactive system has recently received great attention in the experimental study of ultracold chemical reactions, but the corresponding theoretical calculations have not been carried out. Here, we report the first globally accurate ground-state LiNa2 potential energy surface (PES) using a Gaussian process model based on only 1776 actively selected high-level ab initio training points. The constructed PES had high precision and strong generalization capability. On the new PES, the quantum dynamics calculations on the Li(2S) + Na2(v = 0, j = 0) → LiNa + Na reaction were carried out in the 0.001-0.01 eV collision energy range using an improved time-dependent wave packet method. The calculated results indicate that this reaction is dominated by a complex-forming mechanism at low collision energies. The presented dynamics data provide guidance for experimental research, and the newly constructed PES could be further used for ultracold reaction dynamics calculations on this reactive system.
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Affiliation(s)
- Zijiang Yang
- Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams (Ministry of Education), School of Physics, Dalian University of Technology, Dalian 116024, China
| | - Hanghang Chen
- Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams (Ministry of Education), School of Physics, Dalian University of Technology, Dalian 116024, China
| | - Bayaer Buren
- School of Science, Shenyang University of Technology, Shenyang 110870, China
| | - Maodu Chen
- Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams (Ministry of Education), School of Physics, Dalian University of Technology, Dalian 116024, China
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37
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Croft JFE, Jambrina PG, Aoiz FJ, Guo H, Balakrishnan N. Cold Collisions of Ro-Vibrationally Excited D 2 Molecules. J Phys Chem A 2023; 127:1619-1627. [PMID: 36787203 DOI: 10.1021/acs.jpca.2c08855] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
The H2 + H2 system has long been considered a benchmark system for ro-vibrational energy transfer in bimolecular collisions. However, most studies thus far have focused on collisions involving H2 molecules in the ground vibrational level or in the first excited vibrational state. While H2 + H2/HD collisions have received wide attention due to the important role they play in astrophysics, D2 + D2 collisions have received much less attention. Recently, Zhou et al. [ Nat. Chem. 2022, 14, 658-663, DOI: 10.1038/s41557-022-00926-z] examined stereodynamic aspects of rotational energy transfer in collisions of two aligned D2 molecules prepared in the v = 2 vibrational level and j = 2 rotational level. Here, we report quantum calculations of rotational and vibrational energy transfer in collisions of two D2 molecules prepared in vibrational levels up to v = 2 and identify key resonance features that contribute to the angular distribution in the experimental results of Zhou et al. The quantum scattering calculations were performed in full dimensionality and using the rigid-rotor approximation using a recently developed highly accurate six-dimensional potential energy surface for the H4 system that allows descriptions of collisions involving highly vibrationally excited H2 and its isotopologues.
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Affiliation(s)
- James F E Croft
- The Dodd-Walls Centre for Photonic and Quantum Technologies, Dunedin 9016, New Zealand.,Department of Physics, University of Otago, Dunedin 9016, New Zealand
| | - Pablo G Jambrina
- Departamento de Química Física, Universidad de Salamanca, Salamanca 37008, Spain
| | - F Javier Aoiz
- Departamento de Química Física, Universidad Complutense, Madrid 28040, Spain
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - N Balakrishnan
- Department of Chemistry and Biochemistry, University of Nevada, Las Vegas, Nevada 89154, United States
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38
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Studying spin physics with moving molecules. Nature 2023:10.1038/d41586-023-00148-4. [PMID: 36725936 DOI: 10.1038/d41586-023-00148-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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39
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Tunable itinerant spin dynamics with polar molecules. Nature 2023; 614:70-74. [PMID: 36725993 DOI: 10.1038/s41586-022-05479-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 10/25/2022] [Indexed: 02/03/2023]
Abstract
Strongly interacting spins underlie many intriguing phenomena and applications1-4 ranging from magnetism to quantum information processing. Interacting spins combined with motion show exotic spin transport phenomena, such as superfluidity arising from pairing of spins induced by spin attraction5,6. To understand these complex phenomena, an interacting spin system with high controllability is desired. Quantum spin dynamics have been studied on different platforms with varying capabilities7-13. Here we demonstrate tunable itinerant spin dynamics enabled by dipolar interactions using a gas of potassium-rubidium molecules confined to two-dimensional planes, where a spin-1/2 system is encoded into the molecular rotational levels. The dipolar interaction gives rise to a shift of the rotational transition frequency and a collision-limited Ramsey contrast decay that emerges from the coupled spin and motion. Both the Ising and spin-exchange interactions are precisely tuned by varying the strength and orientation of an electric field, as well as the internal molecular state. This full tunability enables both static and dynamical control of the spin Hamiltonian, allowing reversal of the coherent spin dynamics. Our work establishes an interacting spin platform that allows for exploration of many-body spin dynamics and spin-motion physics using the strong, tunable dipolar interaction.
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40
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Christakis L, Rosenberg JS, Raj R, Chi S, Morningstar A, Huse DA, Yan ZZ, Bakr WS. Probing site-resolved correlations in a spin system of ultracold molecules. Nature 2023; 614:64-69. [PMID: 36725998 DOI: 10.1038/s41586-022-05558-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 11/11/2022] [Indexed: 02/03/2023]
Abstract
Synthetic quantum systems with interacting constituents play an important role in quantum information processing and in explaining fundamental phenomena in many-body physics. Following impressive advances in cooling and trapping techniques, ensembles of ultracold polar molecules have emerged as a promising platform that combines several advantageous properties1-11. These include a large set of internal states with long coherence times12-17 and long-range, anisotropic interactions. These features could enable the exploration of intriguing phases of correlated quantum matter, such as topological superfluids18, quantum spin liquids19, fractional Chern insulators20 and quantum magnets21,22. Probing correlations in these phases is crucial to understanding their properties, necessitating the development of new experimental techniques. Here we use quantum gas microscopy23 to measure the site-resolved dynamics of quantum correlations of polar 23Na87Rb molecules confined in a two-dimensional optical lattice. By using two rotational states of the molecules, we realize a spin-1/2 system with dipolar interactions between particles, producing a quantum spin-exchange model21,22,24,25. We study the evolution of correlations during the thermalization process of an out-of-equilibrium spin system for both spatially isotropic and anisotropic interactions. Furthermore, we examine the correlation dynamics of a spin-anisotropic Heisenberg model engineered from the native spin-exchange model by using periodic microwave pulses26-28. These experiments push the frontier of probing and controlling interacting systems of ultracold molecules, with prospects for exploring new regimes of quantum matter and characterizing entangled states that are useful for quantum computation29,30 and metrology31.
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Affiliation(s)
| | | | - Ravin Raj
- Department of Physics, Princeton University, Princeton, NJ, USA
| | - Sungjae Chi
- Department of Physics, Princeton University, Princeton, NJ, USA
| | | | - David A Huse
- Department of Physics, Princeton University, Princeton, NJ, USA
| | - Zoe Z Yan
- Department of Physics, Princeton University, Princeton, NJ, USA
| | - Waseem S Bakr
- Department of Physics, Princeton University, Princeton, NJ, USA.
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41
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Liu L, Yang D, Guo H, Xie D. Full-Dimensional Quantum Dynamics Studies of Ro-vibrationally Inelastic Scattering of H 2O with Ar: A Benchmark Test of the Rigid-Rotor Approximation. J Phys Chem A 2023; 127:195-202. [PMID: 36574615 DOI: 10.1021/acs.jpca.2c07746] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
While the rigid-rotor (RR) approximation is usually considered to be accurate for describing pure rotationally inelastic scattering involving diatoms in their ground or low-lying vibrational states, its validity in scattering involving polyatomic molecules has not been fully examined. The existence of soft/anharmonic vibrational modes in polyatomic molecules could make rotational-vibrational energy transfer rather efficient, thus undermining the premise of the RR approximation. In this work, we conduct a benchmark test of the RR approximation in the rotationally inelastic scattering of the H2O(v2 = 0, 1) + Ar system by comparing with full-dimensional quantum scattering calculations. We demonstrate that the error in the RR rate coefficient for v2 = 0 is less than 5%, while it can reach up to 20% for some initial states within the v2 = 1 manifold. These results indicate that the RR approximation gradually deteriorates with increasing quantum number v2. Vibrational relaxation dynamics of this system was also studied, and it is found that transitions from initial states with a large rotational quantum number of projection on the a principal axis are more efficient. These results shed valuable light on ro-vibrationally inelastic scattering involving polyatomic molecules.
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Affiliation(s)
- Lu Liu
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Dongzheng Yang
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Daiqian Xie
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.,Hefei National Laboratory, Hefei 230088, China
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42
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Dyall KG, Tecmer P, Sunaga A. Diffuse Basis Functions for Relativistic s and d Block Gaussian Basis Sets. J Chem Theory Comput 2023; 19:198-210. [PMID: 36516433 DOI: 10.1021/acs.jctc.2c01050] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Diffuse s, p, and d functions have been optimized for use with previously reported relativistic basis sets for the s and d blocks of the periodic table. The functions were optimized on the 4:1 weighted average of the s2 and p2 configurations of the anion, with the d shell in the dn+1 configuration for the d blocks. Exponents were extrapolated for groups 2 and 12, which have unstable or weakly bound anions. The diffuse basis sets have been tested by application to calculations of electron affinities of the group 11 elements (Cu, Ag, and Au), double electron affinities of the group 11 monocations, and potential energy curves of Mg2 and Ca2 van der Waals dimers, as well as some response properties of the group 1 anions (Rb-, Cs-, and Fr-), the group 2 elements (Sr, Ba, and Ra), and RbLi, CsLi, and FrLi molecules.
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Affiliation(s)
- Kenneth G Dyall
- Dirac Solutions, 10527 NW Lost Park Drive, Portland, Oregon97229, United States
| | - Paweł Tecmer
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University in Torun, Grudziadzka 5, 87-100Torun, Poland
| | - Ayaki Sunaga
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Kumatori, Osaka590-0494, Japan.,Department of Physics, Graduate School of Science, Kyoto University, Kyoto606-8502, Japan
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43
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Chomaz L, Ferrier-Barbut I, Ferlaino F, Laburthe-Tolra B, Lev BL, Pfau T. Dipolar physics: a review of experiments with magnetic quantum gases. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2022; 86:026401. [PMID: 36583342 DOI: 10.1088/1361-6633/aca814] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 12/02/2022] [Indexed: 06/17/2023]
Abstract
Since the achievement of quantum degeneracy in gases of chromium atoms in 2004, the experimental investigation of ultracold gases made of highly magnetic atoms has blossomed. The field has yielded the observation of many unprecedented phenomena, in particular those in which long-range and anisotropic dipole-dipole interactions (DDIs) play a crucial role. In this review, we aim to present the aspects of the magnetic quantum-gas platform that make it unique for exploring ultracold and quantum physics as well as to give a thorough overview of experimental achievements. Highly magnetic atoms distinguish themselves by the fact that their electronic ground-state configuration possesses a large electronic total angular momentum. This results in a large magnetic moment and a rich electronic transition spectrum. Such transitions are useful for cooling, trapping, and manipulating these atoms. The complex atomic structure and large dipolar moments of these atoms also lead to a dense spectrum of resonances in their two-body scattering behaviour. These resonances can be used to control the interatomic interactions and, in particular, the relative importance of contact over dipolar interactions. These features provide exquisite control knobs for exploring the few- and many-body physics of dipolar quantum gases. The study of dipolar effects in magnetic quantum gases has covered various few-body phenomena that are based on elastic and inelastic anisotropic scattering. Various many-body effects have also been demonstrated. These affect both the shape, stability, dynamics, and excitations of fully polarised repulsive Bose or Fermi gases. Beyond the mean-field instability, strong dipolar interactions competing with slightly weaker contact interactions between magnetic bosons yield new quantum-stabilised states, among which are self-bound droplets, droplet assemblies, and supersolids. Dipolar interactions also deeply affect the physics of atomic gases with an internal degree of freedom as these interactions intrinsically couple spin and atomic motion. Finally, long-range dipolar interactions can stabilise strongly correlated excited states of 1D gases and also impact the physics of lattice-confined systems, both at the spin-polarised level (Hubbard models with off-site interactions) and at the spinful level (XYZ models). In the present manuscript, we aim to provide an extensive overview of the various related experimental achievements up to the present.
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Affiliation(s)
- Lauriane Chomaz
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstrasse 25, 6020 Innsbruck, Austria
- Physikalisches Institut der Universität Heidelberg, Im Neuenheimer Feld 226, 69120 Heidelberg, Germany
| | - Igor Ferrier-Barbut
- Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany
- Université Paris-Saclay, Institut d'Optique Graduate School, CNRS, Laboratoire Charles Fabry, 91127 Palaiseau, France
| | - Francesca Ferlaino
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstrasse 25, 6020 Innsbruck, Austria
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, 6020 Innsbruck, Austria
| | - Bruno Laburthe-Tolra
- Université Sorbonne Paris Nord, Laboratoire de Physique des Lasers, F-93430 Villetaneuse, France
- CNRS, UMR 7538, LPL, F-93430 Villetaneuse, France
| | - Benjamin L Lev
- Departments of Physics and Applied Physics and Ginzton Laboratory, Stanford University, Stanford, CA 94305, United States of America
| | - Tilman Pfau
- Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany
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Liu Y, Huang J, Yang D, Xie D, Guo H. Global Full-Dimensional Potential Energy Surface for the Reaction 23Na 87Rb + 23Na 87Rb → 23Na 2 + 87Rb 2 and the Formation Rate and Lifetime of the 23Na 287Rb 2 Collision Complex. J Phys Chem A 2022; 126:9008-9021. [DOI: 10.1021/acs.jpca.2c06438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Yilang Liu
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
| | - Jing Huang
- Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang, Sichuan 621900, China
| | - Dongzheng Yang
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Daiqian Xie
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China
- Hefei National Laboratory, Hefei 230088, China
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
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45
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Lai JM, Sun YJ, Tan QH, Tan PH, Zhang J. Laser Cooling of a Lattice Vibration in van der Waals Semiconductor. NANO LETTERS 2022; 22:7129-7135. [PMID: 35993841 DOI: 10.1021/acs.nanolett.2c02240] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Laser cooling atoms and molecules to ultralow temperatures has produced plenty of opportunities in fundamental physics, precision metrology, and quantum science. Although theoretically proposed over 40 years, the laser cooling of certain lattice vibrations (i.e., phonon) remains a challenge owing to the complexity of solid structures. Here, we demonstrate Raman cooling of a longitudinal optical phonon in two-dimensional semiconductor WS2 by red-detuning excitation at the sideband of the exciton (bound electron-hole pair). Strong coupling between the phonon and exciton and appreciable optomechanical coupling rates provide access to cooling high-frequency phonons that are robust against thermal decoherence even at room temperature. Our experiment opens possibilities of laser cooling and control of individual optical phonon and, eventually, possible cooling of matter in van der Waals semiconductor.
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Affiliation(s)
- Jia-Min Lai
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu-Jia Sun
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qing-Hai Tan
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
| | - Ping-Heng Tan
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jun Zhang
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
- CAS Center of Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100049, China
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46
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Mani D, Roy TK, Khatri J, Schwaab G, Blach S, Hölzl C, Forbert H, Marx D, Havenith M. Internal Electric Field-Induced Formation of Exotic Linear Acetonitrile Chains. J Phys Chem Lett 2022; 13:6852-6858. [PMID: 35861316 DOI: 10.1021/acs.jpclett.2c01482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The application of external electric and magnetic fields is a powerful tool for aligning molecules in a controlled way, if the thermal fluctuations are small. Here we demonstrate that the same holds for internal electric fields in a molecular cluster. The electric field of a single molecular dipole, HCl, is used to manipulate the aggregation mechanism of subsequently added acetonitrile molecules. As a result, we could form exotic linear acetonitrile (CH3CN) chains at 0.37 K, as confirmed by infrared spectroscopy in superfluid helium nanodroplets. These linear chains are not observed in the absence of HCl and can be observed only when the internal electric field created by an HCl molecule is present. The accompanying simulations provide mechanistic insights into steric control, explain the selectivity of the process, and show that non-additive electronic polarization effects systematically enhance the dipole moment of these linear chains. Thus, adding more CH3CN monomers even supports further quasi-linear chain growth.
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Affiliation(s)
- Devendra Mani
- Department of Chemistry, Indian Institute of Technology Kanpur, 208016 Kanpur, India
| | - Tarun Kumar Roy
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Jai Khatri
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Gerhard Schwaab
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Sebastian Blach
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Christoph Hölzl
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Harald Forbert
- Center for Solvation Science ZEMOS, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Dominik Marx
- Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
| | - Martina Havenith
- Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, 44780 Bochum, Germany
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47
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Malla RK, Chernyak VY, Sun C, Sinitsyn NA. Coherent Reaction between Molecular and Atomic Bose-Einstein Condensates: Integrable Model. PHYSICAL REVIEW LETTERS 2022; 129:033201. [PMID: 35905368 DOI: 10.1103/physrevlett.129.033201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 05/01/2022] [Accepted: 06/23/2022] [Indexed: 06/15/2023]
Abstract
We solve a model that describes a stimulated conversion between ultracold bosonic atoms and molecules. The reaction is triggered by a linearly time-dependent transition throughout the Feshbach resonance. Our solution predicts a dependence, with a dynamic phase transition, of the reaction efficiency on the transition rate for both atoms-to-molecule pairing and molecular dissociation processes. We find that for the latter process with a linear energy dispersion of atomic modes, the emerging phase can have a thermalized energy distribution of noninteracting bosons with the temperature defined by the rate of the transition. This provides a simple interpretation of the phase transition in terms of the creation of equilibrium Bose-Einstein condensate.
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Affiliation(s)
- Rajesh K Malla
- Theoretical Division, and the Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Vladimir Y Chernyak
- Department of Chemistry, Wayne State University, 5101 Cass Avenue, Detroit, Michigan 48202, USA
- Department of Mathematics, Wayne State University, 656 W. Kirby, Detroit, Michigan 48202, USA
| | - Chen Sun
- School of Physics and Electronics, Hunan University, Changsha 410082, China
| | - Nikolai A Sinitsyn
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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48
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Schindewolf A, Bause R, Chen XY, Duda M, Karman T, Bloch I, Luo XY. Evaporation of microwave-shielded polar molecules to quantum degeneracy. Nature 2022; 607:677-681. [PMID: 35896646 PMCID: PMC9329123 DOI: 10.1038/s41586-022-04900-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 05/24/2022] [Indexed: 11/11/2022]
Abstract
Ultracold polar molecules offer strong electric dipole moments and rich internal structure, which makes them ideal building blocks to explore exotic quantum matter1-9, implement quantum information schemes10-12 and test the fundamental symmetries of nature13. Realizing their full potential requires cooling interacting molecular gases deeply into the quantum-degenerate regime. However, the intrinsically unstable collisions between molecules at short range have so far prevented direct cooling through elastic collisions to quantum degeneracy in three dimensions. Here we demonstrate evaporative cooling of a three-dimensional gas of fermionic sodium-potassium molecules to well below the Fermi temperature using microwave shielding. The molecules are protected from reaching short range with a repulsive barrier engineered by coupling rotational states with a blue-detuned circularly polarized microwave. The microwave dressing induces strong tunable dipolar interactions between the molecules, leading to high elastic collision rates that can exceed the inelastic ones by at least a factor of 460. This large elastic-to-inelastic collision ratio allows us to cool the molecular gas to 21 nanokelvin, corresponding to 0.36 times the Fermi temperature. Such cold and dense samples of polar molecules open the path to the exploration of many-body phenomena with strong dipolar interactions.
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Affiliation(s)
- Andreas Schindewolf
- Max-Planck-Institut für Quantenoptik, Garching, Germany
- Munich Center for Quantum Science and Technology, Munich, Germany
| | - Roman Bause
- Max-Planck-Institut für Quantenoptik, Garching, Germany
- Munich Center for Quantum Science and Technology, Munich, Germany
| | - Xing-Yan Chen
- Max-Planck-Institut für Quantenoptik, Garching, Germany
- Munich Center for Quantum Science and Technology, Munich, Germany
| | - Marcel Duda
- Max-Planck-Institut für Quantenoptik, Garching, Germany
- Munich Center for Quantum Science and Technology, Munich, Germany
| | - Tijs Karman
- Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands
| | - Immanuel Bloch
- Max-Planck-Institut für Quantenoptik, Garching, Germany
- Munich Center for Quantum Science and Technology, Munich, Germany
- Fakultät für Physik, Ludwig-Maximilians-Universität, Munich, Germany
| | - Xin-Yu Luo
- Max-Planck-Institut für Quantenoptik, Garching, Germany.
- Munich Center for Quantum Science and Technology, Munich, Germany.
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49
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Perera CA, Zuo J, Guo H, Suits AG. Differential Cross Sections for Cold, State-to-State Spin-Orbit Changing Collisions of NO( v = 10) with Neon. J Phys Chem A 2022; 126:3338-3346. [PMID: 35605132 DOI: 10.1021/acs.jpca.2c02698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Inelastic scattering processes have proven a powerful means of investigating molecular interactions, and much current effort is focused on the cold and ultracold regime where quantum phenomena are clearly manifested. Studies of collisions of the open shell nitric oxide (NO) molecule have been central in this effort since the pioneering work of Houston and co-workers in the early 1990s. State-to-state scattering of vibrationally excited molecules in the cold regime introduces challenges that test the suitability of current theoretical methods for ab initio determination of intermolecular potentials, and concomitant electronically nonadiabatic processes raise the bar further. Here we report measurements of differential cross sections for state-to-state spin-orbit changing collisions of NO (v = 10, Ω″ = 1.5, and j″ = 1.5) with neon from 2.3 to 3.5 cm-1 collision energy using our recently developed near-copropagating beam technique. The experimental results are compared with those obtained from quantum scattering calculations on a high-level set of coupled cluster potential energy surfaces and are shown to be in good agreement. The theoretical results suggest that distinct backscattering in the 2.3 cm-1 case arises from overlapping resonances.
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Affiliation(s)
- Chatura A Perera
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, United States
| | - Junxiang Zuo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Arthur G Suits
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, United States
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50
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Lu Y, Holland CM, Cheuk LW. Molecular Laser Cooling in a Dynamically Tunable Repulsive Optical Trap. PHYSICAL REVIEW LETTERS 2022; 128:213201. [PMID: 35687464 DOI: 10.1103/physrevlett.128.213201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 03/31/2022] [Accepted: 05/03/2022] [Indexed: 06/15/2023]
Abstract
Recent work with laser-cooled molecules in attractive optical traps has shown that the differential ac Stark shifts arising from the trap light itself can become problematic, limiting collisional shielding efficiencies, rotational coherence times, and laser-cooling temperatures. In this Letter, we explore trapping and laser cooling of CaF molecules in a ring-shaped repulsive optical trap. The observed dependences of loss rates on temperature and barrier height show characteristic behavior of repulsive traps and indicate strongly suppressed average ac Stark shifts. Within the trap, we find that Λ-enhanced gray molasses cooling is effective, producing similar minimum temperatures as those obtained in free space. By combining in-trap laser cooling with dynamical reshaping of the trap, we also present a method that allows highly efficient and rapid transfer from molecular magneto-optical traps into conventional attractive optical traps, which has been an outstanding challenge for experiments to date. Notably, our method could allow nearly lossless transfer over millisecond timescales.
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Affiliation(s)
- Yukai Lu
- Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
- Department of Electrical and Computer Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - Connor M Holland
- Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
| | - Lawrence W Cheuk
- Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
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