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Anderegg L, Burchesky S, Bao Y, Yu SS, Karman T, Chae E, Ni KK, Ketterle W, Doyle JM. Observation of microwave shielding of ultracold molecules. Science 2021; 373:779-782. [PMID: 34385393 DOI: 10.1126/science.abg9502] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 07/07/2021] [Indexed: 11/03/2022]
Abstract
Harnessing the potential wide-ranging quantum science applications of molecules will require control of their interactions. Here, we used microwave radiation to directly engineer and tune the interaction potentials between ultracold calcium monofluoride (CaF) molecules. By merging two optical tweezers, each containing a single molecule, we probed collisions in three dimensions. The correct combination of microwave frequency and power created an effective repulsive shield, which suppressed the inelastic loss rate by a factor of six, in agreement with theoretical calculations. The demonstrated microwave shielding shows a general route to the creation of long-lived, dense samples of ultracold polar molecules and evaporative cooling.
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Affiliation(s)
- Loïc Anderegg
- Department of Physics, Harvard University, Cambridge, MA, USA. .,Harvard-MIT Center for Ultracold Atoms, Cambridge, MA, USA
| | - Sean Burchesky
- Department of Physics, Harvard University, Cambridge, MA, USA.,Harvard-MIT Center for Ultracold Atoms, Cambridge, MA, USA
| | - Yicheng Bao
- Department of Physics, Harvard University, Cambridge, MA, USA.,Harvard-MIT Center for Ultracold Atoms, Cambridge, MA, USA
| | - Scarlett S Yu
- Department of Physics, Harvard University, Cambridge, MA, USA.,Harvard-MIT Center for Ultracold Atoms, Cambridge, MA, USA
| | - Tijs Karman
- ITAMP, Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA.,Radboud University, Institute for Molecules and Materials, Heijendaalseweg 135, 6525 AJ Nijmegen, Netherlands
| | - Eunmi Chae
- Department of Physics, Korea University, Seongbuk-gu, Seoul, Republic of Korea
| | - Kang-Kuen Ni
- Department of Physics, Harvard University, Cambridge, MA, USA.,Harvard-MIT Center for Ultracold Atoms, Cambridge, MA, USA.,Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Wolfgang Ketterle
- Harvard-MIT Center for Ultracold Atoms, Cambridge, MA, USA.,Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - John M Doyle
- Department of Physics, Harvard University, Cambridge, MA, USA.,Harvard-MIT Center for Ultracold Atoms, Cambridge, MA, USA
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Xie T, Lepers M, Vexiau R, Orbán A, Dulieu O, Bouloufa-Maafa N. Optical Shielding of Destructive Chemical Reactions between Ultracold Ground-State NaRb Molecules. PHYSICAL REVIEW LETTERS 2020; 125:153202. [PMID: 33095632 DOI: 10.1103/physrevlett.125.153202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/09/2020] [Indexed: 06/11/2023]
Abstract
We propose a method to suppress the chemical reactions between ultracold bosonic ground-state ^{23}Na^{87}Rb molecules based on optical shielding. By applying a laser with a frequency blue-detuned from the transition between the lowest rovibrational level of the electronic ground state X^{1}Σ^{+}(v_{X}=0,j_{X}=0), and the long-lived excited level b^{3}Π_{0}(v_{b}=0,j_{b}=1), the long-range dipole-dipole interaction between the colliding molecules can be engineered, leading to a dramatic suppression of reactive and photoinduced inelastic collisions, for both linear and circular laser polarizations. We demonstrate that the spontaneous emission from b^{3}Π_{0}(v_{b}=0,j_{b}=1) does not deteriorate the shielding process. This opens the possibility for a strong increase of the lifetime of cold molecule traps and for an efficient evaporative cooling. We also anticipate that the proposed mechanism is valid for alkali-metal diatomics with sufficiently large dipole-dipole interactions.
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Affiliation(s)
- T Xie
- Université Paris-Saclay, CNRS, Laboratoire Aimé Cotton, 91405 Orsay, France
| | - M Lepers
- Laboratoire Interdisciplinaire Carnot de Bourgogne, CNRS, Université de Bourgogne Franche-Comté, 21078 Dijon, France
| | - R Vexiau
- Université Paris-Saclay, CNRS, Laboratoire Aimé Cotton, 91405 Orsay, France
| | - A Orbán
- Institute for Nuclear Research (ATOMKI), H-4001 Debrecen, Pf. 51, Hungary
| | - O Dulieu
- Université Paris-Saclay, CNRS, Laboratoire Aimé Cotton, 91405 Orsay, France
| | - N Bouloufa-Maafa
- Université Paris-Saclay, CNRS, Laboratoire Aimé Cotton, 91405 Orsay, France
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Lassablière L, Quéméner G. Controlling the Scattering Length of Ultracold Dipolar Molecules. PHYSICAL REVIEW LETTERS 2018; 121:163402. [PMID: 30387665 DOI: 10.1103/physrevlett.121.163402] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Indexed: 06/08/2023]
Abstract
By applying a circularly polarized and slightly blue-detuned microwave field with respect to the first excited rotational state of a dipolar molecule, one can engineer a long-range, shallow potential well in the entrance channel of the two colliding partners. As the applied microwave ac field is increased, the long-range well becomes deeper and can support a certain number of bound states, which in turn bring the value of the molecule-molecule scattering length from a large negative value to a large positive one. We adopt an adimensional approach where the molecules are described by a rescaled rotational constant B[over ˜]=B/s_{E_{3}} where s_{E_{3}} is a characteristic dipolar energy. We found that molecules with B[over ˜]>10^{8} are immune to any quenching losses when a sufficient ac field is applied, the ratio elastic to quenching processes can reach values above 10^{3}, and that the value and sign of the scattering length can be tuned. The ability to control the molecular scattering length opens the door for a rich, strongly correlated, many-body physics for ultracold molecules, similar to that for ultracold atoms.
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Affiliation(s)
- Lucas Lassablière
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, ENS Paris-Saclay, Université Paris-Saclay, 91405 Orsay, France
| | - Goulven Quéméner
- Laboratoire Aimé Cotton, CNRS, Université Paris-Sud, ENS Paris-Saclay, Université Paris-Saclay, 91405 Orsay, France
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Yurovsky VA, Ben-Reuven A. Channel Interference in Optical Collisions of Cold Atom Beams. J Phys Chem A 1998. [DOI: 10.1021/jp9819902] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Zilio SC, Marcassa L, Muniz S, Horowicz R, Bagnato V, Napolitano R, Weiner J, Julienne PS. Polarization dependence of optical suppression in photoassociative ionization collisions in a sodium magneto-optic trap. PHYSICAL REVIEW LETTERS 1996; 76:2033-2036. [PMID: 10060589 DOI: 10.1103/physrevlett.76.2033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Suominen K, Burnett K, Julienne PS. Role of off-resonant excitation in cold collisions in a strong laser field. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1996; 53:R1220-R1223. [PMID: 9913096 DOI: 10.1103/physreva.53.r1220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Suominen K, Burnett K, Julienne PS, Walhout M, Sterr U, Orzel C, Hoogerland M, Rolston SL. Ultracold collisions and optical shielding in metastable xenon. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1996; 53:1678-1689. [PMID: 9913060 DOI: 10.1103/physreva.53.1678] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Sanchez-Villicana V, Gensemer SD, Tan KY, Kumarakrishnan A, Dinneen TP, Süptitz W, Gould PL. Suppression of ultracold ground-state hyperfine-changing collisions with laser light. PHYSICAL REVIEW LETTERS 1995; 74:4619-4622. [PMID: 10058556 DOI: 10.1103/physrevlett.74.4619] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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