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Li W, Zhang Z, Niu X, He D, Xing W, Zhang Y. Diabatic Potential Energy Surfaces of SrH 2+ and Dynamics Studies of the Sr +(5s 2S) + H 2 Reaction. J Phys Chem A 2024. [PMID: 39093206 DOI: 10.1021/acs.jpca.4c03648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/04/2024]
Abstract
Based on the ab initio energy points of both ground and excited states, a neural network fitting method combined with a specific function was successfully used to construct the diabatic potential energy surfaces (PESs) of the SrH2+ system. The topographical features of the diabatic PESs were examined in detail. The results indicate that the nonadiabatic transition characteristics between ground and excited states are accurately described by the newly constructed diabatic PESs. To verify the validity and applicability of the diabatic PESs, as well as the nonadiabatic effects during the reaction process, the quantum dynamics studies of the Sr+(5s2S) + H2 reaction were performed based on both adiabatic and diabatic PESs. The dynamics results indicate that adiabatic dynamics results are dozens of times larger than those of nonadiabatic. This illustrates the significant effect of nonadiabaticity, indicating that adiabatic dynamics results often overestimate the actual values. The integral cross sections (ICSs) were calculated and compared with the experimental data. The diabatic ICSs are in good agreement with the experimental results. The reasonable dynamics results indicate that the newly constructed diabatic PESs are suitable for the relevant dynamics studies.
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Affiliation(s)
- Wentao Li
- Weifang University of Science and Technology, Shouguang 262700, China
| | - Zhijun Zhang
- Weifang University of Science and Technology, Shouguang 262700, China
| | - Xianghong Niu
- School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210003, China
| | - Di He
- Weifang University of Science and Technology, Shouguang 262700, China
| | - Wei Xing
- College of Physics and Electronic Engineering, Xinyang Normal University, Xinyang 464000, China
| | - Yong Zhang
- Department of Physics, Tonghua Normal University, Tonghua ,Jilin134002, China
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2
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Zhang J. Highly efficient creation and detection of deeply bound molecules via invariant-based inverse engineering with feasible modified drivings. J Chem Phys 2024; 160:024104. [PMID: 38189609 DOI: 10.1063/5.0183063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2023] [Accepted: 12/15/2023] [Indexed: 01/09/2024] Open
Abstract
Stimulated Raman Adiabatic Passage (STIRAP) and its variants, such as M-type chainwise-STIRAP, allow for efficiently transferring the populations in a multilevel system and have widely been used to prepare molecules in their rovibrational ground state. However, their transfer efficiencies are generally imperfect. The main obstacle is the presence of losses and the requirement to make the dynamics adiabatic. To this end, in the present paper, a new theoretical method is proposed for the efficient and robust creation and detection of deeply bound molecules in three-level Λ-type and five-level M-type systems via "Invariant-based shortcut-to-adiabaticity." In the regime of large detunings, we first reduce the dynamics of three- and five-level molecular systems to those of effective two- and three-level counterparts. By doing so, the major molecular losses from the excited states can be well suppressed. Consequently, the effective two-level counterpart can be directly compatible with two different "Invariant-based Inverse Engineering" protocols; the results show that both protocols give a comparable performance and have a good experimental feasibility. For the effective three-level counterpart, by considering a relation among the four incident pulses, we show that this model can be further generalized to an effective Λ-type one with the simplest resonant coupling. This generalized model permits us to borrow the "Invariant-based Inverse Engineering" protocol from a standard three-level Λ-type system to a five-level M-type system. Numerical calculations show that the weakly bound molecules can be efficiently transferred to their deeply bound states without strong laser pulses, and the stability against parameter variations is well preserved. Finally, the detection of ultracold deeply bound molecules is discussed.
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Affiliation(s)
- Jiahui Zhang
- School of Physics, East China University of Science and Technology, Shanghai 200237, China
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3
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A Feshbach resonance in collisions between triplet ground-state molecules. Nature 2023; 614:54-58. [PMID: 36725997 DOI: 10.1038/s41586-022-05635-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 12/06/2022] [Indexed: 02/03/2023]
Abstract
Collisional resonances are important tools that have been used to modify interactions in ultracold gases, for realizing previously unknown Hamiltonians in quantum simulations1, for creating molecules from atomic gases2 and for controlling chemical reactions. So far, such resonances have been observed for atom-atom collisions, atom-molecule collisions3-7 and collisions between Feshbach molecules, which are very weakly bound8-10. Whether such resonances exist for ultracold ground-state molecules has been debated owing to the possibly high density of states and/or rapid decay of the resonant complex11-15. Here we report a very pronounced and narrow (25 mG) Feshbach resonance in collisions between two triplet ground-state NaLi molecules. This molecular Feshbach resonance has two special characteristics. First, the collisional loss rate is enhanced by more than two orders of magnitude above the background loss rate, which is saturated at the p-wave universal value, owing to strong chemical reactivity. Second, the resonance is located at a magnetic field where two open channels become nearly degenerate. This implies that the intermediate complex predominantly decays to the second open channel. We describe the resonant loss feature using a model with coupled modes that is analogous to a Fabry-Pérot cavity. Our observations provide strong evidence for the existence of long-lived coherent intermediate complexes even in systems without reaction barriers and open up the possibility of coherent control of chemical reactions.
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4
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Hai Y, Li LH, Li JL, Wang GR, Cong SL. Formation of ultracold 39K 133Cs molecules via Feshbach optimized photoassociation. J Chem Phys 2020; 152:174307. [PMID: 32384849 DOI: 10.1063/5.0001794] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A Feshbach optimized photoassociation (FOPA) process for preparing ultracold excited-state 39K133Cs molecules is studied theoretically. Under the joint action of the magnetic field and short laser pulse, the colliding atoms in a superposition state composed of eight hyperfine components are converted into a molecule in the vibrational level of the excited state via two transition processes, the transition between singlet states and the transition between triplet states. The association efficiency can be significantly enhanced by taking advantage of Feshbach resonance. At different resonance positions, different hyperfine components of the superposition state dominate over the FOPA process, and the quantum interference displays different behaviors. Compared with the FOPA process only including a single hyperfine component, the quantum interference in the FOPA process containing all hyperfine components has a visible effect on the association efficiency.
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Affiliation(s)
- Yang Hai
- School of Physics, Dalian University of Technology, Dalian 116024, China
| | - Li-Hang Li
- School of Physics, Dalian University of Technology, Dalian 116024, China
| | - Jing-Lun Li
- School of Physics, Dalian University of Technology, Dalian 116024, China
| | - Gao-Ren Wang
- School of Physics, Dalian University of Technology, Dalian 116024, China
| | - Shu-Lin Cong
- School of Physics, Dalian University of Technology, Dalian 116024, China
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5
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Baier S, Petter D, Becher JH, Patscheider A, Natale G, Chomaz L, Mark MJ, Ferlaino F. Realization of a Strongly Interacting Fermi Gas of Dipolar Atoms. PHYSICAL REVIEW LETTERS 2018; 121:093602. [PMID: 30230905 DOI: 10.1103/physrevlett.121.093602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Indexed: 06/08/2023]
Abstract
We realize a two-component dipolar Fermi gas with tunable interactions, using erbium atoms. Employing a lattice-protection technique, we selectively prepare deeply degenerate mixtures of the two lowest spin states and perform high-resolution Feshbach spectroscopy in an optical dipole trap. We identify a comparatively broad Feshbach resonance and map the interspin scattering length in its vicinity. The Fermi mixture shows a remarkable collisional stability in the strongly interacting regime, providing a first step towards studies of superfluid pairing, crossing from Cooper pairs to bound molecules, in presence of dipole-dipole interactions.
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Affiliation(s)
- S Baier
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - D Petter
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - J H Becher
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - A Patscheider
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, 6020 Innsbruck, Austria
| | - G Natale
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - L Chomaz
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
| | - M J Mark
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, 6020 Innsbruck, Austria
| | - F Ferlaino
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, 6020 Innsbruck, Austria
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6
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Shi D, Liu X, Shan S, Xu H, Yan B. Configuration interaction study on the low-lying electronic states of strontium hydride cation including spin-orbit coupling. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 180:29-36. [PMID: 28264788 DOI: 10.1016/j.saa.2017.02.054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 02/17/2017] [Accepted: 02/22/2017] [Indexed: 06/06/2023]
Abstract
Ab initio calculations on low-lying electronic states of strontium hydride cations, SrH+, have been performed using the internally contracted multi-reference configuration interaction (icMRCI) method with Davidson correction (+Q). Spin-orbit coupling (SOC) effect between the singlet and triplet states of SrH+ has been investigated for the first time. The potential energy curves (PECs) of a total of 12 Λ-S states, as well as the 23 Ω states generated from the Λ-S states after considering the SOC effect, have been calculated. The spectroscopic constants and transition properties, including the transition dipole moments, the Franck-Condon factors, and the radiative lifetimes, have been obtained based on the calculated PECs. It indicates that the SOC effect plays a non-negligible role in electronic states of SrH+. Our study should shed light on the structure and behavior of low-lying electronic states and should pave further experimental studies on the spectroscopy of strontium hydride cations.
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Affiliation(s)
- Dandan Shi
- Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy (Jilin University), Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
| | - Xiaoting Liu
- Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy (Jilin University), Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
| | - Shimin Shan
- Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy (Jilin University), Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
| | - Haifeng Xu
- Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy (Jilin University), Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China.
| | - Bing Yan
- Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy (Jilin University), Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China.
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7
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Reichsöllner L, Schindewolf A, Takekoshi T, Grimm R, Nägerl HC. Quantum Engineering of a Low-Entropy Gas of Heteronuclear Bosonic Molecules in an Optical Lattice. PHYSICAL REVIEW LETTERS 2017; 118:073201. [PMID: 28256882 DOI: 10.1103/physrevlett.118.073201] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Indexed: 06/06/2023]
Abstract
We demonstrate a generally applicable technique for mixing two-species quantum degenerate bosonic samples in the presence of an optical lattice, and we employ it to produce low-entropy samples of ultracold ^{87}Rb^{133}Cs Feshbach molecules with a lattice filling fraction exceeding 30%. Starting from two spatially separated Bose-Einstein condensates of Rb and Cs atoms, Rb-Cs atom pairs are efficiently produced by using the superfluid-to-Mott insulator quantum phase transition twice, first for the Cs sample, then for the Rb sample, after nulling the Rb-Cs interaction at a Feshbach resonance's zero crossing. We form molecules out of atom pairs and characterize the mixing process in terms of sample overlap and mixing speed. The dense and ultracold sample of more than 5000 RbCs molecules is an ideal starting point for experiments in the context of quantum many-body physics with long-range dipolar interactions.
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Affiliation(s)
- Lukas Reichsöllner
- Institut für Experimentalphysik, Universität Innsbruck, 6020 Innsbruck, Austria
| | - Andreas Schindewolf
- Institut für Experimentalphysik, Universität Innsbruck, 6020 Innsbruck, Austria
| | - Tetsu Takekoshi
- Institut für Experimentalphysik, Universität Innsbruck, 6020 Innsbruck, Austria
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, 6020 Innsbruck, Austria
| | - Rudolf Grimm
- Institut für Experimentalphysik, Universität Innsbruck, 6020 Innsbruck, Austria
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, 6020 Innsbruck, Austria
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8
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Pazyuk EA, Zaitsevskii AV, Stolyarov AV, Tamanis M, Ferber R. Laser synthesis of ultracold alkali metal dimers: optimization and control. RUSSIAN CHEMICAL REVIEWS 2015. [DOI: 10.1070/rcr4534] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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9
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Bergmann K, Vitanov NV, Shore BW. Perspective: Stimulated Raman adiabatic passage: The status after 25 years. J Chem Phys 2015; 142:170901. [PMID: 25956078 DOI: 10.1063/1.4916903] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The first presentation of the STIRAP (stimulated Raman adiabatic passage) technique with proper theoretical foundation and convincing experimental data appeared 25 years ago, in the May 1st, 1990 issue of The Journal of Chemical Physics. By now, the STIRAP concept has been successfully applied in many different fields of physics, chemistry, and beyond. In this article, we comment briefly on the initial motivation of the work, namely, the study of reaction dynamics of vibrationally excited small molecules, and how this initial idea led to the documented success. We proceed by providing a brief discussion of the physics of STIRAP and how the method was developed over the years, before discussing a few examples from the amazingly wide range of applications which STIRAP now enjoys, with the aim to stimulate further use of the concept. Finally, we mention some promising future directions.
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Affiliation(s)
- Klaas Bergmann
- Fachbereich Physik und Forschungszentrum OPTIMAS, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Nikolay V Vitanov
- Department of Physics, St. Kliment Ohridski University of Sofia, James Bourchier 5 Blvd., 1164 Sofia, Bulgaria
| | - Bruce W Shore
- 618 Escondido Circle, Livermore, California 94550, USA
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10
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HU XUEJIN, ZHANG WEI, HUANG YIN, YANG JUNFENG, CONG SHULIN. FORMATION OF ULTRACOLD CESIUM MOLECULES IN THE GROUND ELECTRONIC STATE. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2012. [DOI: 10.1142/s0219633612500897] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We investigate theoretically the preparation of ultracold photoassociated Cs 2 molecules in the lowest vibrational level of the ground electronic state via the stimulated Raman adiabatic passage (STIRAP) by solving the time-dependent Schrödinger equation using the mapped Fourier grid method. A negative chirped laser pulse is used to produce the unstable photoassociated molecules in the excited electronic state. A dump pulse is utilized to transfer a partial population of the unstable photoassociated molecules to the vibrational v″ = 18 level of the ground electronic state. This part of population is then transferred to the v″ = 0 level of the ground electronic state by the pump and Stokes laser pulses via an intermediate state which is taken to be the v′ = 7 level of the excited electronic state, forming the stable photoassociated molecules. The population transfer efficiency from v″ = 18 to v″ = 0 in the ground electronic state reaches 96.2% via the STIRAP.
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Affiliation(s)
- XUE-JIN HU
- School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, P. R. China
| | - WEI ZHANG
- School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, P. R. China
| | - YIN HUANG
- School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, P. R. China
| | - JUN-FENG YANG
- School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, P. R. China
| | - SHU-LIN CONG
- School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024, P. R. China
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11
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Stellmer S, Pasquiou B, Grimm R, Schreck F. Creation of ultracold Sr(2) molecules in the electronic ground state. PHYSICAL REVIEW LETTERS 2012; 109:115302. [PMID: 23005642 DOI: 10.1103/physrevlett.109.115302] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Indexed: 06/01/2023]
Abstract
We report on the creation of ultracold (84)Sr(2) molecules in the electronic ground state. The molecules are formed from atom pairs on sites of an optical lattice using stimulated Raman adiabatic passage (STIRAP). We achieve a transfer efficiency of 30% and obtain 4×10(4) molecules with full control over the external and internal quantum state. STIRAP is performed near the narrow (1)S(0)-(3)P(1) intercombination transition, using a vibrational level of the 1(0(u)(+)) potential as an intermediate state. In preparation of our molecule association scheme, we have determined the binding energies of the last vibrational levels of the 1(0(u)(+)), 1(1(u)) excited-state and the X (1)Σ(g)(+) ground-state potentials. Our work overcomes the previous limitation of STIRAP schemes to systems with magnetic Feshbach resonances, thereby establishing a route that is applicable to many systems beyond alkali-metal dimers.
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Affiliation(s)
- Simon Stellmer
- Institut für Quantenoptik und Quanteninformation, Österreichische Akademie der Wissenschaften, 6020 Innsbruck, Austria
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12
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Affiliation(s)
- Goulven Quéméner
- JILA, University of Colorado,
Boulder, CO 80309-0440, United States
| | - Paul S. Julienne
- Joint Quantum Institute, NIST
and the University of Maryland, Gaithersburg, Maryland 20899-8423,
United States
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13
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Affiliation(s)
- Christiane P. Koch
- Theoretische Physik, Universität Kassel, Heinrich-Plett-Strasse 40,
34132 Kassel, Germany
| | - Moshe Shapiro
- Department
of Chemistry, University of British Columbia, Vancouver, Canada V6T
1Z1, and Department of Chemical Physics, The Weizmann Institute, Rehovot, Israel 76100
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14
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Byrd JN, Harvey Michels H, Montgomery JA, Côté R, Stwalley WC. Structure, energetics, and reactions of alkali tetramers. J Chem Phys 2012; 136:014306. [DOI: 10.1063/1.3672646] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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16
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Wells N, Lane IC. Prospects for ultracold carbon via charge exchange reactions and laser cooled carbides. Phys Chem Chem Phys 2011; 13:19036-51. [PMID: 21971563 DOI: 10.1039/c1cp21304k] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Strategies to produce an ultracold sample of carbon atoms are explored and assessed with the help of quantum chemistry. After a brief discussion of the experimental difficulties using conventional methods, two strategies are investigated. The first attempts to exploit charge exchange reactions between ultracold metal atoms and sympathetically cooled C(+) ions. Ab initio calculations including electron correlation have been conducted on the molecular ions [LiC](+) and [BeC](+) to determine whether alkali or alkaline earth metals are a suitable buffer gas for the formation of C atoms but strong spontaneous radiative charge exchange ensure they are not ideal. The second technique involves the stimulated production of ultracold C atoms from a gas of laser cooled carbides. Calculations on LiC suggest that the alkali carbides are not suitable but the CH radical is a possible laser cooling candidate thanks to very favourable Frank-Condon factors. A scheme based on a four pulse STIRAP excitation pathway to a Feshbach resonance is outlined for the production of atomic fragments with near zero centre of mass velocity.
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Affiliation(s)
- Nathan Wells
- Innovative Molecular Materials Group, School of Chemistry and Chemical Engineering, Queen's University of Belfast, Stranmillis Road, Belfast, UK BT9 5AG
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17
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Zillich RE, Whaley KB. Homogeneous Bose gas of dipolar molecules in the mean field approximation. Phys Chem Chem Phys 2011; 13:18835-43. [DOI: 10.1039/c1cp21331h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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18
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Soldán P. Potential energy surface for spin-polarized rubidium trimer. J Chem Phys 2010; 132:234308. [DOI: 10.1063/1.3455710] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Ospelkaus S, Ni KK, Quéméner G, Neyenhuis B, Wang D, de Miranda MHG, Bohn JL, Ye J, Jin DS. Controlling the hyperfine state of rovibronic ground-state polar molecules. PHYSICAL REVIEW LETTERS 2010; 104:030402. [PMID: 20366634 DOI: 10.1103/physrevlett.104.030402] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Revised: 11/12/2009] [Indexed: 05/29/2023]
Abstract
We report the preparation of a rovibronic ground-state molecular quantum gas in a single hyperfine state and, in particular, the absolute lowest quantum state. This addresses the last internal degree of freedom remaining after the recent production of a near quantum degenerate gas of molecules in their rovibronic ground state, and provides a crucial step towards full control over molecular quantum gases. We demonstrate a scheme that is general for bialkali polar molecules and allows the preparation of molecules in a single hyperfine state or in an arbitrary coherent superposition of hyperfine states. The scheme relies on electric-dipole, two-photon microwave transitions through rotationally excited states and makes use of electric nuclear quadrupole interactions to transfer molecular population between different hyperfine states.
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Affiliation(s)
- S Ospelkaus
- JILA, National Institute of Standards and Technology and University of Colorado, and Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, USA
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20
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Danzl JG, Mark MJ, Haller E, Gustavsson M, Bouloufa N, Dulieu O, Ritsch H, Hart R, Nägerl HC. Precision molecular spectroscopy for ground state transfer of molecular quantum gases. Faraday Discuss 2009; 142:283-95; discussion 319-34. [DOI: 10.1039/b820542f] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Ospelkaus S, Ni KK, de Miranda MHG, Neyenhuis B, Wang D, Kotochigova S, Julienne PS, Jin DS, Ye J. Ultracold polar molecules near quantum degeneracy. Faraday Discuss 2009; 142:351-9; discussion 429-61. [DOI: 10.1039/b821298h] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Julienne PS. Ultracold molecules from ultracold atoms: a case study with the KRb molecule. Faraday Discuss 2009; 142:361-88; discussion 429-61. [DOI: 10.1039/b820917k] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Ni KK, Ospelkaus S, de Miranda MHG, Pe'er A, Neyenhuis B, Zirbel JJ, Kotochigova S, Julienne PS, Jin DS, Ye J. A High Phase-Space-Density Gas of Polar Molecules. Science 2008; 322:231-5. [DOI: 10.1126/science.1163861] [Citation(s) in RCA: 1446] [Impact Index Per Article: 90.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- K.-K. Ni
- JILA, National Institute of Standards and Technology (NIST) and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309–0440, USA
- Physics Department, Temple University, Philadelphia, PA 19122–6082, USA
- Joint Quantum Institute, NIST, and University of Maryland, Gaithersburg, MD 20899–8423, USA
| | - S. Ospelkaus
- JILA, National Institute of Standards and Technology (NIST) and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309–0440, USA
- Physics Department, Temple University, Philadelphia, PA 19122–6082, USA
- Joint Quantum Institute, NIST, and University of Maryland, Gaithersburg, MD 20899–8423, USA
| | - M. H. G. de Miranda
- JILA, National Institute of Standards and Technology (NIST) and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309–0440, USA
- Physics Department, Temple University, Philadelphia, PA 19122–6082, USA
- Joint Quantum Institute, NIST, and University of Maryland, Gaithersburg, MD 20899–8423, USA
| | - A. Pe'er
- JILA, National Institute of Standards and Technology (NIST) and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309–0440, USA
- Physics Department, Temple University, Philadelphia, PA 19122–6082, USA
- Joint Quantum Institute, NIST, and University of Maryland, Gaithersburg, MD 20899–8423, USA
| | - B. Neyenhuis
- JILA, National Institute of Standards and Technology (NIST) and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309–0440, USA
- Physics Department, Temple University, Philadelphia, PA 19122–6082, USA
- Joint Quantum Institute, NIST, and University of Maryland, Gaithersburg, MD 20899–8423, USA
| | - J. J. Zirbel
- JILA, National Institute of Standards and Technology (NIST) and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309–0440, USA
- Physics Department, Temple University, Philadelphia, PA 19122–6082, USA
- Joint Quantum Institute, NIST, and University of Maryland, Gaithersburg, MD 20899–8423, USA
| | - S. Kotochigova
- JILA, National Institute of Standards and Technology (NIST) and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309–0440, USA
- Physics Department, Temple University, Philadelphia, PA 19122–6082, USA
- Joint Quantum Institute, NIST, and University of Maryland, Gaithersburg, MD 20899–8423, USA
| | - P. S. Julienne
- JILA, National Institute of Standards and Technology (NIST) and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309–0440, USA
- Physics Department, Temple University, Philadelphia, PA 19122–6082, USA
- Joint Quantum Institute, NIST, and University of Maryland, Gaithersburg, MD 20899–8423, USA
| | - D. S. Jin
- JILA, National Institute of Standards and Technology (NIST) and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309–0440, USA
- Physics Department, Temple University, Philadelphia, PA 19122–6082, USA
- Joint Quantum Institute, NIST, and University of Maryland, Gaithersburg, MD 20899–8423, USA
| | - J. Ye
- JILA, National Institute of Standards and Technology (NIST) and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309–0440, USA
- Physics Department, Temple University, Philadelphia, PA 19122–6082, USA
- Joint Quantum Institute, NIST, and University of Maryland, Gaithersburg, MD 20899–8423, USA
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24
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Lang F, Winkler K, Strauss C, Grimm R, Denschlag JH. Ultracold triplet molecules in the rovibrational ground state. PHYSICAL REVIEW LETTERS 2008; 101:133005. [PMID: 18851446 DOI: 10.1103/physrevlett.101.133005] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Indexed: 05/26/2023]
Abstract
We report here on the production of an ultracold gas of tightly bound Rb2 triplet molecules in the rovibrational ground state, close to quantum degeneracy. This is achieved by optically transferring weakly bound Rb2 molecules to the absolute lowest level of the ground triplet potential with a transfer efficiency of about 90%. The transfer takes place in a 3D optical lattice which traps a sizeable fraction of the tightly bound molecules with a lifetime exceeding 200 ms.
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Affiliation(s)
- F Lang
- Institut für Experimentalphysik und Zentrum für Quantenphysik, Universität Innsbruck, A-6020 Innsbruck, Austria
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25
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Deiglmayr J, Grochola A, Repp M, Mörtlbauer K, Glück C, Lange J, Dulieu O, Wester R, Weidemüller M. Formation of ultracold polar molecules in the rovibrational ground state. PHYSICAL REVIEW LETTERS 2008; 101:133004. [PMID: 18851445 DOI: 10.1103/physrevlett.101.133004] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2008] [Indexed: 05/26/2023]
Abstract
Ultracold LiCs molecules in the absolute ground state X1Sigma+, v'' = 0, J'' = 0 are formed via a single photoassociation step starting from laser-cooled atoms. The selective production of v'' = 0, J'' = 2 molecules with a 50-fold higher rate is also demonstrated. The rotational and vibrational state of the ground state molecules is determined in a setup combining depletion spectroscopy with resonant-enhanced multiphoton ionization time-of-flight spectroscopy. Using the determined production rate of up to 5 x 10(3) molecules/s, we describe a simple scheme which can provide large samples of externally and internally cold dipolar molecules.
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Affiliation(s)
- J Deiglmayr
- Albert-Ludwigs-Universität Freiburg, Physikalisches Institut, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
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26
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Danzl JG, Haller E, Gustavsson M, Mark MJ, Hart R, Bouloufa N, Dulieu O, Ritsch H, Nagerl HC. Quantum Gas of Deeply Bound Ground State Molecules. Science 2008; 321:1062-6. [DOI: 10.1126/science.1159909] [Citation(s) in RCA: 303] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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27
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Junker M, Dries D, Welford C, Hitchcock J, Chen YP, Hulet RG. Photoassociation of a Bose-Einstein condensate near a Feshbach resonance. PHYSICAL REVIEW LETTERS 2008; 101:060406. [PMID: 18764443 DOI: 10.1103/physrevlett.101.060406] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Indexed: 05/26/2023]
Abstract
We measure the effect of a magnetic Feshbach resonance (FR) on the rate and light-induced frequency shift of a photoassociation resonance in ultracold 7Li. The photoassociation-induced loss-rate coefficient K_{p} depends strongly on magnetic field, varying by more than a factor of 10;{4} for fields near the FR. At sufficiently high laser intensities, K_{p} for a thermal gas decreases with increasing intensity, while saturation is observed for the first time in a Bose-Einstein condensate. The frequency shift is also strongly field dependent and exhibits an anomalous blueshift for fields just below the FR.
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Affiliation(s)
- M Junker
- Department of Physics and Astronomy and Rice Quantum Institute, Rice University, Houston, Texas 77251, USA
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28
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Pellegrini P, Gacesa M, Côté R. Giant formation rates of ultracold molecules via Feshbach-optimized photoassociation. PHYSICAL REVIEW LETTERS 2008; 101:053201. [PMID: 18764389 DOI: 10.1103/physrevlett.101.053201] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Indexed: 05/26/2023]
Abstract
Ultracold molecules offer a broad variety of applications, ranging from metrology to quantum computing. However, forming "real" ultracold molecules, i.e., in deeply bound levels, is a very difficult proposition. Here, we show how photoassociation in the vicinity of a Feshbach resonance enhances molecular formation rates by several orders of magnitude. We illustrate this effect in heteronuclear systems, and find giant rate coefficients even in deeply bound levels. We also give a simple analytical expression for the photoassociation rate and discuss future applications of the Feshbach-optimized photoassociation technique.
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Affiliation(s)
- Philippe Pellegrini
- Department of Physics U-3046, University of Connecticut, Storrs, CT 06269-3046, USA
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29
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Viteau M, Chotia A, Allegrini M, Bouloufa N, Dulieu O, Comparat D, Pillet P. Optical Pumping and Vibrational Cooling of Molecules. Science 2008; 321:232-4. [DOI: 10.1126/science.1159496] [Citation(s) in RCA: 231] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Matthieu Viteau
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, Bâtiment 505, 91405 Orsay, France
- Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3,56127 Pisa, Italy
| | - Amodsen Chotia
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, Bâtiment 505, 91405 Orsay, France
- Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3,56127 Pisa, Italy
| | - Maria Allegrini
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, Bâtiment 505, 91405 Orsay, France
- Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3,56127 Pisa, Italy
| | - Nadia Bouloufa
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, Bâtiment 505, 91405 Orsay, France
- Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3,56127 Pisa, Italy
| | - Olivier Dulieu
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, Bâtiment 505, 91405 Orsay, France
- Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3,56127 Pisa, Italy
| | - Daniel Comparat
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, Bâtiment 505, 91405 Orsay, France
- Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3,56127 Pisa, Italy
| | - Pierre Pillet
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, Bâtiment 505, 91405 Orsay, France
- Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, Dipartimento di Fisica, Università di Pisa, Largo Pontecorvo 3,56127 Pisa, Italy
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30
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Salzmann W, Mullins T, Eng J, Albert M, Wester R, Weidemüller M, Merli A, Weber SM, Sauer F, Plewicki M, Weise F, Wöste L, Lindinger A. Coherent transients in the femtosecond photoassociation of ultracold molecules. PHYSICAL REVIEW LETTERS 2008; 100:233003. [PMID: 18643493 DOI: 10.1103/physrevlett.100.233003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2007] [Indexed: 05/26/2023]
Abstract
We demonstrate the photoassociation of ultracold rubidium dimers using coherent femtosecond pulses. Starting from a cloud of ultracold rubidium atoms, electronically excited rubidium molecules are formed with shaped photoassociation pump pulses. The excited state molecules are projected with a time-delayed probe pulse onto molecular ion states which are detected in a mass spectrometer. Coherent transient oscillations of the excited state population are observed in the wings of the pump pulse, in agreement with the time-dependent solution of the Schrödinger equation of the excitation process.
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Affiliation(s)
- W Salzmann
- Physikalisches Institut, Universität Freiburg, Freiburg im Breisgau, Germany
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31
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Knoop S, Mark M, Ferlaino F, Danzl JG, Kraemer T, Nägerl HC, Grimm R. Metastable feshbach molecules in high rotational states. PHYSICAL REVIEW LETTERS 2008; 100:083002. [PMID: 18352621 DOI: 10.1103/physrevlett.100.083002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Indexed: 05/26/2023]
Abstract
We experimentally demonstrate Cs2 Feshbach molecules well above the dissociation threshold, which are stable against spontaneous decay on the time scale of 1 s. An optically trapped sample of ultracold dimers is prepared in a high rotational state and magnetically tuned into a region with a negative binding energy. The metastable character of these molecules arises from the large centrifugal barrier in combination with negligible coupling to states with low rotational angular momentum. A sharp onset of dissociation with increasing magnetic field is mediated by a crossing with a lower rotational dimer state and facilitates dissociation on demand with a well-defined energy.
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Affiliation(s)
- S Knoop
- Institut für Experimentalphysik and Forschungszentrum für Quantenphysik, Universität Innsbruck, 6020 Innsbruck, Austria
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32
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DeMille D, Sainis S, Sage J, Bergeman T, Kotochigova S, Tiesinga E. Enhanced Sensitivity to Variation of m(e)/m(p) in molecular spectra. PHYSICAL REVIEW LETTERS 2008; 100:043202. [PMID: 18352268 DOI: 10.1103/physrevlett.100.043202] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2007] [Indexed: 05/26/2023]
Abstract
We propose new experiments with high sensitivity to a possible variation of the electron-to-proton mass ratio mu identical with m(e)/m(p). We consider a nearly degenerate pair of molecular vibrational levels, each associated with a different electronic potential. With respect to a change in mu, the change in the splitting between such levels can be large both on an absolute scale and relative to the splitting. We demonstrate the existence of such pairs of states in Cs2, where the narrow spectral lines achievable with ultracold molecules make the system promising for future searches for small variations in mu.
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Affiliation(s)
- D DeMille
- Department of Physics, Yale University, New Haven, Connecticut 06520, USA
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33
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Kleinert J, Haimberger C, Zabawa PJ, Bigelow NP. Trapping of ultracold polar molecules with a thin-wire electrostatic trap. PHYSICAL REVIEW LETTERS 2007; 99:143002. [PMID: 17930666 DOI: 10.1103/physrevlett.99.143002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2007] [Indexed: 05/25/2023]
Abstract
We describe the realization of a dc electric-field trap for ultracold polar molecules, the thin-wire electrostatic trap (TWIST). The thin wires that form the electrodes of the TWIST allow us to superimpose the trap onto a magneto-optical trap (MOT). In our experiment, ultracold polar NaCs molecules in their electronic ground state are created in the MOT via photoassociation, achieving a continuous accumulation in the TWIST of molecules in low-field seeking states. Initial measurements show that the TWIST trap lifetime is limited only by the background pressure in the chamber.
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Affiliation(s)
- J Kleinert
- Department of Physics and Astronomy, and The Laboratory for Laser Energetics, The University of Rochester, Rochester, NY 14627, USA
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34
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Iskin M, Sá de Melo CAR. Ultracold heteronuclear molecules and ferroelectric superfluids. PHYSICAL REVIEW LETTERS 2007; 99:110402. [PMID: 17930415 DOI: 10.1103/physrevlett.99.110402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Revised: 04/19/2007] [Indexed: 05/25/2023]
Abstract
We analyze the possibility of a ferroelectric transition in heteronuclear molecules consisting of Bose-Bose, Bose-Fermi, or Fermi-Fermi atom pairs. This transition is characterized by the appearance of a spontaneous electric polarization below a critical temperature. We discuss the existence of a ferroelectric Fermi liquid phase for Fermi molecules and the existence of a ferroelectric superfluid phase for Bose molecules characterized by the coexistence of ferroelectric and superfluid orders. Lastly, we propose an experiment to detect ferroelectric correlations through the observation of coherent dipole radiation pulses.
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Affiliation(s)
- M Iskin
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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35
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Mark M, Kraemer T, Waldburger P, Herbig J, Chin C, Nägerl HC, Grimm R. "Stückelberg interferometry" with ultracold molecules. PHYSICAL REVIEW LETTERS 2007; 99:113201. [PMID: 17930437 DOI: 10.1103/physrevlett.99.113201] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Indexed: 05/25/2023]
Abstract
We report on the realization of a time-domain "Stückelberg interferometer", which is based on the internal-state structure of ultracold Feshbach molecules. Two subsequent passages through a weak avoided crossing between two different orbital angular momentum states in combination with a variable hold time lead to high-contrast population oscillations. This allows for a precise determination of the energy difference between the two molecular states. We demonstrate a high degree of control over the interferometer dynamics. The interferometric scheme provides new possibilities for precision measurements with ultracold molecules.
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Affiliation(s)
- M Mark
- Institut für Experimentalphysik und Forschungszentrum für Quantenphysik, Universität Innsbruck, 6020 Innsbruck, Austria
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36
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Pe'er A, Shapiro EA, Stowe MC, Shapiro M, Ye J. Precise control of molecular dynamics with a femtosecond frequency comb. PHYSICAL REVIEW LETTERS 2007; 98:113004. [PMID: 17501050 DOI: 10.1103/physrevlett.98.113004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2006] [Indexed: 05/15/2023]
Abstract
We present a general and highly efficient scheme for performing narrow-band Raman transitions between molecular vibrational levels using a coherent train of weak pump-dump pairs of shaped ultrashort pulses. The use of weak pulses permits an analytic description within the framework of coherent control in the perturbative regime, while coherent accumulation of many pulse pairs enables near unity transfer efficiency with a high spectral selectivity, thus forming a powerful combination of pump-dump control schemes and the precision of the frequency comb. Simulations verify the feasibility and robustness of this concept, with the aim to form deeply bound, ultracold molecules.
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Affiliation(s)
- Avi Pe'er
- JILA, National Institute of Standards and Technology, University of Colorado, Boulder, Colorado 80309-0440, USA
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