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Zhang AX, Zhang W, Qin YH, Hu XW, Qiao X, Xue JK. Nonlinear Bloch dynamics and spin-wave generation in a Bose-Hubbard ladder subject to effective magnetic field. Phys Rev E 2022; 106:044215. [PMID: 36397576 DOI: 10.1103/physreve.106.044215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
The two-leg magnetic ladder is the simplest and ideal model to reflect the coupling effects of lattice and magnetic field. It is of great significance to study some novel phases, topological characteristics, and chiral characteristics in condensed matter physics. In particular, the left-right leg degree of freedom can be regarded as a pseudospin, and the two-leg magnetic ladder also provides an ideal platform for the study of spin dynamics. Here the ground state, Bloch oscillations (BOs), and spin dynamics of the interacting two-leg magnetic ladder subject to an external linear force are studied by using variational approach and numerical simulation. In the absence of the external linear force, the critical condition of transition between the zero-momentum state and plane-wave state is obtained analytically, and the physical mechanism of the ground-state transition is revealed. When the external linear force presents, the occurrence of BOs excites the spin dynamics, and we reveal the chiral BOs and the accompanied spin dynamics of the system in different ground states. In particular, we further study the influence of periodically modulated linear force on BOs and spin dynamics. The frequencies of the linear force corresponding to the resonances and pseudoresonances are obtained analytically, which result in rich nonlinear dynamics. In resonances, stable and strong BOs (with larger amplitude) are observed. In pseudoresonances, because the pseudoresonance frequencies are related to the initial momentum and phase of the wave packet, a dispersion effect takes place and strong diffusion of wave packet occurs. When the frequency is nonresonant, drift and weak dispersion of wave packet occur simultaneously with the wave-packet oscillation. In all cases, the wave-packet dynamics is accompanied with periodic but anharmonic pseudospin oscillation. The BOs and spin dynamics are effectively controlled by periodically modulating the linear force.
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Affiliation(s)
- Ai-Xia Zhang
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou, 730070, China
| | - Wei Zhang
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou, 730070, China
| | - Ya-Hui Qin
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou, 730070, China
| | - Xiao-Wen Hu
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou, 730070, China
| | - Xin Qiao
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou, 730070, China
| | - Ju-Kui Xue
- College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou, 730070, China
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2
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Lin Z, Liu C, Chen Y. Novel Quantum Phases of Two-Component Bosons with Pair Hopping in Synthetic Dimension. PHYSICAL REVIEW LETTERS 2020; 125:245301. [PMID: 33412032 DOI: 10.1103/physrevlett.125.245301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 08/20/2020] [Accepted: 11/06/2020] [Indexed: 06/12/2023]
Abstract
We study two-component (or pseudospin-1/2) bosons with pair hopping interactions in synthetic dimension, for which a feasible experimental scheme on a square optical lattice is also presented. Previous studies have shown that two-component bosons with on-site interspecies interaction can only generate nontrivial interspecies paired superfluid (super-counter-fluidity or pair-superfluid) states. In contrast, apart from interspecies paired superfluid, we reveal two new phases by considering this additional pair hopping interaction. These novel phases are intraspecies paired superfluid (molecular superfluid) and an exotic noninteger Mott insulator which shows a noninteger atom number at each site for each species, but an integer for total atom number.
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Affiliation(s)
- Zhi Lin
- Department of Physics and State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
- School of Physics and Materials Science, Anhui University, Hefei 230601, China
| | - Chenrong Liu
- Department of Physics and State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
| | - Yan Chen
- Department of Physics and State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
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3
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Bhowmik A, Haldar SK, Alon OE. Impact of the transverse direction on the many-body tunneling dynamics in a two-dimensional bosonic Josephson junction. Sci Rep 2020; 10:21476. [PMID: 33293575 PMCID: PMC7722723 DOI: 10.1038/s41598-020-78173-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Accepted: 10/29/2020] [Indexed: 11/08/2022] Open
Abstract
Tunneling in a many-body system appears as one of the novel implications of quantum physics, in which particles move in space under an otherwise classically-forbidden potential barrier. Here, we theoretically describe the quantum dynamics of the tunneling phenomenon of a few intricate bosonic clouds in a closed system of a two-dimensional symmetric double-well potential. We examine how the inclusion of the transverse direction, orthogonal to the junction of the double-well, can intervene in the tunneling dynamics of bosonic clouds. We use a well-known many-body numerical method, called the multiconfigurational time-dependent Hartree for bosons (MCTDHB) method. MCTDHB allows one to obtain accurately the time-dependent many-particle wavefunction of the bosons which in principle entails all the information of interest about the system under investigation. We analyze the tunneling dynamics by preparing the initial state of the bosonic clouds in the left well of the double-well either as the ground, longitudinally or transversely excited, or a vortex state. We unravel the detailed mechanism of the tunneling process by analyzing the evolution in time of the survival probability, depletion and fragmentation, and the many-particle position, momentum, and angular-momentum expectation values and their variances. As a general rule, all objects lose coherence while tunneling through the barrier and the states which include transverse excitations do so faster. In particular for the later states, we show that even when the transverse direction is seemingly frozen, prominent many-body dynamics in a two-dimensional bosonic Josephson junction occurs. Implications are briefly discussed.
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Affiliation(s)
- Anal Bhowmik
- Department of Mathematics, University of Haifa, Haifa, 3498838, Israel.
- Haifa Research Center for Theoretical Physics and Astrophysics, University of Haifa, Haifa, 3498838, Israel.
| | - Sudip Kumar Haldar
- Department of Mathematics, University of Haifa, Haifa, 3498838, Israel
- Haifa Research Center for Theoretical Physics and Astrophysics, University of Haifa, Haifa, 3498838, Israel
- Department of Physics, SRM University Delhi-NCR, Plot No. 39 Rajiv Gandhi education city, Sonipat, 131029, India
| | - Ofir E Alon
- Department of Mathematics, University of Haifa, Haifa, 3498838, Israel
- Haifa Research Center for Theoretical Physics and Astrophysics, University of Haifa, Haifa, 3498838, Israel
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4
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Yan M, Hui HY, Rigol M, Scarola VW. Equilibration Dynamics of Strongly Interacting Bosons in 2D Lattices with Disorder. PHYSICAL REVIEW LETTERS 2017; 119:073002. [PMID: 28949694 DOI: 10.1103/physrevlett.119.073002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Indexed: 06/07/2023]
Abstract
Motivated by recent optical lattice experiments [J.-y. Choi et al., Science 352, 1547 (2016)SCIEAS0036-807510.1126/science.aaf8834], we study the dynamics of strongly interacting bosons in the presence of disorder in two dimensions. We show that Gutzwiller mean-field theory (GMFT) captures the main experimental observations, which are a result of the competition between disorder and interactions. Our findings highlight the difficulty in distinguishing glassy dynamics, which can be captured by GMFT, and many-body localization, which cannot be captured by GMFT, and indicate the need for further experimental studies of this system.
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Affiliation(s)
- Mi Yan
- Department of Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - Hoi-Yin Hui
- Department of Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - Marcos Rigol
- Department of Physics, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - V W Scarola
- Department of Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
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5
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Compagno E, De Chiara G, Angelakis DG, Palma GM. Tunable Polarons in Bose-Einstein Condensates. Sci Rep 2017; 7:2355. [PMID: 28539580 PMCID: PMC5443808 DOI: 10.1038/s41598-017-02398-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 03/27/2017] [Indexed: 11/09/2022] Open
Abstract
A toolbox for the quantum simulation of polarons in ultracold atoms is presented. Motivated by the impressive experimental advances in the area of ultracold atomic mixtures, we theoretically study the problem of ultracold atomic impurities immersed in a Bose-Einstein condensate mixture (BEC). The coupling between impurity and BEC gives rise to the formation of polarons whose mutual interaction can be effectively tuned using an external laser driving a quasi-resonant Raman transition between the BEC components. Our scheme allows one to change the effective interactions between polarons in different sites from attractive to zero. This is achieved by simply changing the intensity and the frequency of the two lasers. Such arrangement opens new avenues for the study of strongly correlated condensed matter models in ultracold gases.
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Affiliation(s)
- E Compagno
- Department of Physics and Astronomy, University College London, Gower Street, WC1E 6BT, London, United Kingdom
| | - G De Chiara
- Centre for Theoretical Atomic, Molecular and Optical Physics Queen's University, Belfast, BT7 1NN, United Kingdom.
| | - D G Angelakis
- School of Electronic and Computer Engineering, Technical University of Crete, Chania, Crete, 73100, Greece.,Centre for Quantum Technologies, National University of Singapore, 2 Science Drive 3, Singapore, 117542, Singapore
| | - G M Palma
- NEST-INFM (CNR) and Dipartimento di Fisica e Chimica Università degli Studi di Palermo, Via Archirafi 36, I-90123, Palermo, Italy
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6
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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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7
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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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8
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Chotia A, Neyenhuis B, Moses SA, Yan B, Covey JP, Foss-Feig M, Rey AM, Jin DS, Ye J. Long-lived dipolar molecules and Feshbach molecules in a 3D optical lattice. PHYSICAL REVIEW LETTERS 2012; 108:080405. [PMID: 22463505 DOI: 10.1103/physrevlett.108.080405] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Indexed: 05/31/2023]
Abstract
We have realized long-lived ground-state polar molecules in a 3D optical lattice, with a lifetime of up to 25 s, which is limited only by off-resonant scattering of the trapping light. Starting from a 2D optical lattice, we observe that the lifetime increases dramatically as a small lattice potential is added along the tube-shaped lattice traps. The 3D optical lattice also dramatically increases the lifetime for weakly bound Feshbach molecules. For a pure gas of Feshbach molecules, we observe a lifetime of greater than 20 s in a 3D optical lattice; this represents a 100-fold improvement over previous results. This lifetime is also limited by off-resonant scattering, the rate of which is related to the size of the Feshbach molecule. Individually trapped Feshbach molecules in the 3D lattice can be converted to pairs of K and Rb atoms and back with nearly 100% efficiency.
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Affiliation(s)
- Amodsen Chotia
- JILA, National Institute of Standards and Technology and University of Colorado, Department of Physics, University of Colorado, Boulder, Colorado 80309-0440, USA
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9
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Julienne PS, Hanna TM, Idziaszek Z. Universal ultracold collision rates for polar molecules of two alkali-metal atoms. Phys Chem Chem Phys 2011; 13:19114-24. [DOI: 10.1039/c1cp21270b] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Hen I, Rigol M. Strongly interacting atom lasers in three-dimensional optical lattices. PHYSICAL REVIEW LETTERS 2010; 105:180401. [PMID: 21231090 DOI: 10.1103/physrevlett.105.180401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2010] [Indexed: 05/30/2023]
Abstract
We show that the dynamical melting of a Mott insulator in a three-dimensional lattice leads to condensation at nonzero momenta, a phenomenon that can be used to generate strongly interacting atom lasers in optical lattices. For infinite on-site repulsion, the case considered here, the momenta at which bosons condense are determined analytically and found to have a simple dependence on the hopping amplitudes. The occupation of the condensates is shown to scale linearly with the total number of atoms in the initial Mott insulator. Our results are obtained by using a Gutzwiller-type mean-field approach, gauged against exact-diagonalization solutions of small systems.
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Affiliation(s)
- Itay Hen
- Department of Physics, Georgetown University, Washington, D.C. 20057, USA
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11
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Affiliation(s)
- Jeremy M. Hutson
- a Department of Chemistry , University of Durham , South Road, Durham , DH1 3LE , England
| | - Pavel Soldán
- b Faculty of Nuclear Sciences and Physical Engineering , Department of Physics , Doppler Institute , Czech Technical University , Břehová 7 , 115 19 Praha 1 , Czech Republic
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12
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Byczuk K, Hofstetter W, Vollhardt D. Competition between Anderson localization and antiferromagnetism in correlated lattice fermion systems with disorder. PHYSICAL REVIEW LETTERS 2009; 102:146403. [PMID: 19392461 DOI: 10.1103/physrevlett.102.146403] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Indexed: 05/27/2023]
Abstract
The magnetic ground state phase diagram of the disordered Hubbard model at half-filling is computed in dynamical mean-field theory supplemented with the spin resolved, typical local density of states. The competition between many-body correlations and disorder is found to stabilize paramagnetic and antiferromagnetic metallic phases at weak interactions. Strong disorder leads to Anderson localization of the electrons and suppresses the antiferromagnetic long-range order. Slater and Heisenberg antiferromagnets respond characteristically differently to disorder. The results can be tested with cold fermionic atoms loaded into optical lattices.
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Affiliation(s)
- Krzysztof Byczuk
- Theoretical Physics III, Center for Electronic Correlations and Magnetism, Institute for Physics, University of Augsburg, D-86135 Augsburg, Germany
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13
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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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14
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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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15
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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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16
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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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17
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Kotochigova S. Prospects for making polar molecules with microwave fields. PHYSICAL REVIEW LETTERS 2007; 99:073003. [PMID: 17930893 DOI: 10.1103/physrevlett.99.073003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2007] [Indexed: 05/25/2023]
Abstract
We propose a mechanism to produce ultracold polar molecules with microwave fields. It converts trapped ultracold atoms into vibrationally excited molecules by a single microwave transition and entirely depends on the existence of a permanent dipole moment in the molecules. As opposed to production of molecules by photoassociation or magnetic-field Feshbach resonances, our method does not rely on properties of excited states or existence of Feshbach resonances. We determine conditions for optimal creation of polar molecules in vibrationally excited states of the ground-state potential by changing frequency and intensity of the microwave field. We also explore the possibility to produce vibrationally cold molecules by combining the microwave field with an optical Raman transition or by applying a microwave field to Feshbach molecules. The production mechanism is illustrated for KRb and RbCs.
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Affiliation(s)
- Svetlana Kotochigova
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122-6082, USA
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18
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Luu T, Schwenk A. Three-fermion problems in optical lattices. PHYSICAL REVIEW LETTERS 2007; 98:103202. [PMID: 17358531 DOI: 10.1103/physrevlett.98.103202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2006] [Indexed: 05/14/2023]
Abstract
We present exact results for the spectra of three fermionic atoms in a single well of an optical lattice. For the three lowest hyperfine states of 6Li atoms, we find a Borromean state across the region of the distinct pairwise Feshbach resonances. For 40K atoms, nearby Feshbach resonances are known for two of the pairs, and a bound three-body state develops towards the positive scattering-length side. In addition, we study the sensitivity of our results to atomic details. The predicted few-body phenomena can be realized in optical lattices in the limit of low tunneling.
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Affiliation(s)
- T Luu
- N Division, Lawrence Livermore National Laboratory, Livermore, California 94551, USA.
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19
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Tikhonenkov I, Vardi A. Confinement effects on the stimulated dissociation of molecular Bose-Einstein condensates. PHYSICAL REVIEW LETTERS 2007; 98:080403. [PMID: 17359073 DOI: 10.1103/physrevlett.98.080403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2006] [Indexed: 05/14/2023]
Abstract
We show that a molecular Bose-Einstein condensate in a trap is stabilized against stimulated dissociation if the trap size is smaller than the resonance healing length (Planck's 2/2mgsqrt[n]);1/2. The condensate shape determines the critical atom-molecule coupling frequency. We discuss an experiment for triggering dissociation by a sudden change of coupling or trap parameters. This effect demonstrates one of the unique collective features of "superchemistry" in that the yield of a chemical reaction depends critically on the size and shape of the reaction vessel.
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Affiliation(s)
- Igor Tikhonenkov
- Department of Chemistry, Ben-Gurion University of the Negev, P.O.B. 653, Beer-Sheva 84105, Israel
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20
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Winkler K, Lang F, Thalhammer G, Straten PVD, Grimm R, Denschlag JH. Coherent optical transfer of Feshbach molecules to a lower vibrational state. PHYSICAL REVIEW LETTERS 2007; 98:043201. [PMID: 17358763 DOI: 10.1103/physrevlett.98.043201] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Indexed: 05/14/2023]
Abstract
Using the technique of stimulated Raman adiabatic passage (STIRAP) we have coherently transferred ultracold (87)Rb(2) Feshbach molecules into a more deeply bound vibrational quantum level. Our measurements indicate a high transfer efficiency of up to 87%. Because the molecules are held in an optical lattice with not more than a single molecule per lattice site, inelastic collisions between the molecules are suppressed and we observe long molecular lifetimes of about 1 s. Using STIRAP we have created quantum superpositions of the two molecular states and tested their coherence interferometrically. These results represent an important step towards Bose-Einstein condensation of molecules in the vibrational ground state.
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Affiliation(s)
- K Winkler
- Institut für Experimentalphysik, Forschungszentrum für Quantenphysik, Universität Innsbruck, 6020 Innsbruck, Austria
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21
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22
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Zheng Y, Kostrun M, Javanainen J. Low-acceleration instability of a Bose-Einstein condensate in an optical lattice. PHYSICAL REVIEW LETTERS 2004; 93:230401. [PMID: 15601128 DOI: 10.1103/physrevlett.93.230401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2004] [Indexed: 05/24/2023]
Abstract
We study a Bose-Einstein condensate in a one-dimensional accelerated optical lattice using the mean-field version of the Bose-Hubbard model. Reminiscent of recent experiments [M. Cristiani et al., Opt. Express 12, 4 (2004)], we find a new type of an instability in this system that occurs in the limit when the acceleration is small.
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Affiliation(s)
- Yi Zheng
- Department of Physics, University of Connecticut, Storrs, CT 06269-3046, USA
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23
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Micheli A, Daley AJ, Jaksch D, Zoller P. Single atom transistor in a 1D optical lattice. PHYSICAL REVIEW LETTERS 2004; 93:140408. [PMID: 15524777 DOI: 10.1103/physrevlett.93.140408] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2004] [Indexed: 05/24/2023]
Abstract
We propose a scheme utilizing a quantum interference phenomenon to switch the transport of atoms in a 1D optical lattice through a site containing an impurity atom. The impurity represents a qubit which in one spin state is transparent to the probe atoms, but in the other acts as a single atom mirror. This allows a single-shot quantum nondemolition measurement of the qubit spin.
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Affiliation(s)
- A Micheli
- Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, A-6020 Innsbruck, Austria
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24
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Rom T, Best T, Mandel O, Widera A, Greiner M, Hänsch TW, Bloch I. State selective production of molecules in optical lattices. PHYSICAL REVIEW LETTERS 2004; 93:073002. [PMID: 15324231 DOI: 10.1103/physrevlett.93.073002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2004] [Indexed: 05/24/2023]
Abstract
We demonstrate quantum control over both internal and external quantum degrees of freedom in a high number of identical "chemical reactions," carried out in an array of microtraps in a 3D optical lattice. Starting from a Mott insulating phase of an ultracold atomic quantum gas, we use two-photon Raman transitions to create molecules on lattice sites occupied by two atoms. In the atom-molecule conversion process, we can control both the internal rovibronic and external center of mass quantum state of the molecules. The lattice isolates the microscopic chemical reactions from each other, thereby allowing photoassociation spectra without collisional broadening even at high densities of up to 2 x 10(15) cm(-3).
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Affiliation(s)
- Tim Rom
- Ludwig-Maximilians-Universität, Schellingstrasse 4/III, 80799 Munich, Germany
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25
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Xu K, Mukaiyama T, Abo-Shaeer JR, Chin JK, Miller DE, Ketterle W. Formation of quantum-degenerate sodium molecules. PHYSICAL REVIEW LETTERS 2003; 91:210402. [PMID: 14683282 DOI: 10.1103/physrevlett.91.210402] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2003] [Indexed: 05/24/2023]
Abstract
Ultracold sodium molecules were produced from an atomic Bose-Einstein condensate by ramping an applied magnetic field across a Feshbach resonance. More than 10(5) molecules were generated with a conversion efficiency of approximately 4%. Using laser light resonant with an atomic transition, the remaining atoms could be selectively removed, preventing fast collisional relaxation of the molecules. Time-of-flight analysis of the pure molecular sample yielded an instantaneous phase-space density greater than 20.
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Affiliation(s)
- K Xu
- Department of Physics, MIT-Harvard Center for Ultracold Atoms, and Research Laboratory of Electronics, MIT, Cambridge, Massachusetts 02139, USA
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26
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Search CP, Zhang W, Meystre P. Molecular micromaser. PHYSICAL REVIEW LETTERS 2003; 91:190401. [PMID: 14611570 DOI: 10.1103/physrevlett.91.190401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2003] [Indexed: 05/24/2023]
Abstract
We show that photoassociation of fermionic atoms into bosonic molecules inside an optical lattice can be described using a Jaynes-Cummings Hamiltonian with a nonlinear detuning. Using this equivalence to the Jaynes-Cummings dynamics, we show how one can construct a micromaser for the molecular field in each lattice site.
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Affiliation(s)
- Chris P Search
- Optical Sciences Center, The University of Arizona, Tucson, AZ 85721, USA
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Stock R, Deutsch IH, Bolda EL. Quantum state control via trap-induced shape resonance in ultracold atomic collisions. PHYSICAL REVIEW LETTERS 2003; 91:183201. [PMID: 14611281 DOI: 10.1103/physrevlett.91.183201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2003] [Indexed: 05/24/2023]
Abstract
We investigate controlled collisions between trapped but separated ultracold atoms. The interaction between atoms is treated self-consistently using an energy-dependent delta-function pseudopotential model, whose validity we establish. At a critical separation, a "trap-induced shape resonance" between molecular bound states and a vibrational eigenstate of the trap can occur. This resonance leads to an avoided crossing in the eigenspectrum as a function of separation. We investigate how this new resonance can be employed for quantum control.
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Affiliation(s)
- René Stock
- Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131, USA.
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Herbig J, Kraemer T, Mark M, Weber T, Chin C, Nägerl HC, Grimm R. Preparation of a pure molecular quantum gas. Science 2003; 301:1510-3. [PMID: 12934014 DOI: 10.1126/science.1088876] [Citation(s) in RCA: 335] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
An ultracold molecular quantum gas is created by application of a magnetic field sweep across a Feshbach resonance to a Bose-Einstein condensate of cesium atoms. The ability to separate the molecules from the atoms permits direct imaging of the pure molecular sample. Magnetic levitation enables study of the dynamics of the ensemble on extended time scales. We measured ultralow expansion energies in the range of a few nanokelvin for a sample of 3000 molecules. Our observations are consistent with the presence of a macroscopic molecular matter wave.
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Affiliation(s)
- Jens Herbig
- Institut für Experimentalphysik, Universität Innsbruck, Technikerstrabetae 25, 6020 Innsbruck, Austria
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Damski B, Zakrzewski J, Santos L, Zoller P, Lewenstein M. Atomic Bose and Anderson glasses in optical lattices. PHYSICAL REVIEW LETTERS 2003; 91:080403. [PMID: 14525226 DOI: 10.1103/physrevlett.91.080403] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2003] [Indexed: 05/24/2023]
Abstract
An ultracold atomic Bose gas in an optical lattice is shown to provide an ideal system for the controlled analysis of disordered Bose lattice gases. This goal may be easily achieved under the current experimental conditions by introducing a pseudorandom potential created by a second additional lattice or, alternatively, by placing a speckle pattern on the main lattice. We show that, for a noncommensurable filling factor, in the strong-interaction limit, a controlled growing of the disorder drives a dynamical transition from superfluid to Bose-glass phase. Similarly, in the weak interaction limit, a dynamical transition from superfluid to Anderson-glass phase may be observed. In both regimes, we show that even very low-intensity disorder-inducing lasers cause large modifications of the superfluid fraction of the system.
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Affiliation(s)
- B Damski
- Instytut Fizyki imienia Mariana Smoluchowskiego, Uniwersytet Jagielloński, Reymonta 4, PL-30 059 Kraków, Poland
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Esslinger T, Mølmer K. Atoms and molecules in lattices: Bose-Einstein condensates built on a shared vacuum. PHYSICAL REVIEW LETTERS 2003; 90:160406. [PMID: 12731965 DOI: 10.1103/physrevlett.90.160406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2002] [Indexed: 05/24/2023]
Abstract
In optical lattices where each site is occupied in its lowest energy state by a superposition of zero, one, and two atoms, one can in a controllable manner convert the atomic pair into a molecule while retaining the vacuum and one-atom amplitudes. The microscopic quantum coherence on each site between the vacuum and the single molecule component leads to a macroscopically populated molecular condensate when the lattice is removed.
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Affiliation(s)
- Tilman Esslinger
- Institute for Quantum Electronics, ETH Zurich, CH-8093 Zurich, Switzerland
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Damski B, Santos L, Tiemann E, Lewenstein M, Kotochigova S, Julienne P, Zoller P. Creation of a dipolar superfluid in optical lattices. PHYSICAL REVIEW LETTERS 2003; 90:110401. [PMID: 12688917 DOI: 10.1103/physrevlett.90.110401] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2002] [Indexed: 05/24/2023]
Abstract
We show that, by loading a Bose-Einstein condensate of two different atomic species into an optical lattice, it is possible to achieve a Mott-insulator phase with exactly one atom of each species per lattice site. A subsequent photoassociation leads to the formation of one heteronuclear molecule with a large electric dipole moment, at each lattice site. The melting of such a dipolar Mott insulator creates a dipolar superfluid, and eventually a dipolar molecular condensate.
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Affiliation(s)
- B Damski
- Institut für Theoretische Physik, Universität Hannover, Germany
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Mølmer K. Jaynes-Cummings dynamics with a matter wave oscillator. PHYSICAL REVIEW LETTERS 2003; 90:110403. [PMID: 12688919 DOI: 10.1103/physrevlett.90.110403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2002] [Indexed: 05/24/2023]
Abstract
We propose to subject two Bose-Einstein condensates to a periodic potential, so that one condensate undergoes the Mott-insulator transition to a state with precisely one atom per lattice site. We show that photoassociation of heteronuclear molecules within each lattice site is described by the quantum optical Jaynes-Cummings Hamiltonian. In analogy with studies of this Hamiltonian with cavity fields and trapped ions, we are thus able to engineer quantum optical states of atomic matter wave fields and we are able to reconstruct these states by quantum state tomography.
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Affiliation(s)
- Klaus Mølmer
- QUANTOP, Danish National Research Foundation Center for Quantum Optics, Department of Physics and Astronomy, University of Aarhus, DK-8000 Arhus C, Denmark
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Scott RG, Martin AM, Fromhold TM, Bujkiewicz S, Sheard FW, Leadbeater M. Creation of solitons and vortices by bragg reflection of Bose-Einstein condensates in an optical lattice. PHYSICAL REVIEW LETTERS 2003; 90:110404. [PMID: 12688920 DOI: 10.1103/physrevlett.90.110404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2002] [Indexed: 05/24/2023]
Abstract
We study the dynamics of Bose-Einstein condensates in an optical lattice and harmonic trap. The condensates are set in motion by displacing the trap and initially follow simple semiclassical paths, shaped by the lowest energy band. Above a critical displacement, the condensate undergoes Bragg reflection. For high atom densities, the first Bragg reflection generates a train of solitons and vortices, which destabilize the condensate and trigger explosive expansion. At lower densities, soliton and vortex formation requires multiple Bragg reflections, and damps the center-of-mass motion.
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Affiliation(s)
- R G Scott
- School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, United Kingdom
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