Pub Date : 2020-07-01DOI: 10.1103/PHYSREVA.103.L021301
Dong-Chen Zheng, Chun-Rong Ye, Lin Wen, R. Liao
We consider a homogeneous mixture of bosons and polarized fermions. We find that long-range and attractive fermion-mediated interactions between bosons have dramatic effects on the properties of the bosons. We construct the phase diagram spanned by boson-fermion mass ratio and boson-fermion scattering parameter. It consists of stable region of mixing and unstable region toward phase separation. In stable mixing phase, the collective long-wavelength excitations can either be well-behaved with infinite lifetime or be finite in lifetime suffered from the Landau damping. We examine the effects of the induced interaction on the properties of weakly interacting bosons. It turns out that the induced interaction not only enhances the repulsion between the bosons against collapse but also enhances the stability of the superfluid state by suppressing quantum depletion.
{"title":"Polarizing the medium: Fermion-mediated interactions between bosons","authors":"Dong-Chen Zheng, Chun-Rong Ye, Lin Wen, R. Liao","doi":"10.1103/PHYSREVA.103.L021301","DOIUrl":"https://doi.org/10.1103/PHYSREVA.103.L021301","url":null,"abstract":"We consider a homogeneous mixture of bosons and polarized fermions. We find that long-range and attractive fermion-mediated interactions between bosons have dramatic effects on the properties of the bosons. We construct the phase diagram spanned by boson-fermion mass ratio and boson-fermion scattering parameter. It consists of stable region of mixing and unstable region toward phase separation. In stable mixing phase, the collective long-wavelength excitations can either be well-behaved with infinite lifetime or be finite in lifetime suffered from the Landau damping. We examine the effects of the induced interaction on the properties of weakly interacting bosons. It turns out that the induced interaction not only enhances the repulsion between the bosons against collapse but also enhances the stability of the superfluid state by suppressing quantum depletion.","PeriodicalId":8838,"journal":{"name":"arXiv: Quantum Gases","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89604952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.31349/RevMexFis.66.388
D. Hernandez-Rajkov, J. E. Padilla-Castillo, M. Mendoza-López, R. Col'in-Rodr'iguez, A. Gutiérrez-Valdés, S. A. Morales-Ram'irez, R. A. Guti'errez-Arenas, C. A. Gardea-Flores, R. Jáuregui-Renaud, J. A. Seman, F. J. Poveda-Cuevas, G. Roati
We present our experimental setup to produce ultracold strongly correlated fermionic superfluids made of a two-component spin-mixture of $^6$Li atoms. Employing standard cooling techniques, we achieve quantum degeneracy in a single-beam optical dipole trap. Our setup is capable of generating spin-balanced samples at temperatures as low as $T/T_F = 0.1$ containing up to $5 times 10^4$ atomic pairs. We can access different superfluid regimes by tuning the interparticle interactions close to a broad magnetic Feshbach resonance. In particular, we are able to explore the crossover from the molecular Bose-Einstein condensate (BEC) to the Bardeen-Cooper-Schrieffer (BCS) superfluid regimes.
{"title":"Experimental setup for the production of ultracold strongly correlated fermionic superfluids of 6Li","authors":"D. Hernandez-Rajkov, J. E. Padilla-Castillo, M. Mendoza-López, R. Col'in-Rodr'iguez, A. Gutiérrez-Valdés, S. A. Morales-Ram'irez, R. A. Guti'errez-Arenas, C. A. Gardea-Flores, R. Jáuregui-Renaud, J. A. Seman, F. J. Poveda-Cuevas, G. Roati","doi":"10.31349/RevMexFis.66.388","DOIUrl":"https://doi.org/10.31349/RevMexFis.66.388","url":null,"abstract":"We present our experimental setup to produce ultracold strongly correlated fermionic superfluids made of a two-component spin-mixture of $^6$Li atoms. Employing standard cooling techniques, we achieve quantum degeneracy in a single-beam optical dipole trap. Our setup is capable of generating spin-balanced samples at temperatures as low as $T/T_F = 0.1$ containing up to $5 times 10^4$ atomic pairs. We can access different superfluid regimes by tuning the interparticle interactions close to a broad magnetic Feshbach resonance. In particular, we are able to explore the crossover from the molecular Bose-Einstein condensate (BEC) to the Bardeen-Cooper-Schrieffer (BCS) superfluid regimes.","PeriodicalId":8838,"journal":{"name":"arXiv: Quantum Gases","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75063224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-30DOI: 10.1103/PHYSREVRESEARCH.3.013173
N. Masalaeva, W. Niedenzu, F. Mivehvar, H. Ritsch
We study the zero-temperature quantum phase diagram for a two-component Bose-Einstein condensate in an optical cavity. The two atomic spin states are Raman coupled by two transverse orthogonally-polarized, blue detuned plane-wave lasers inducing a repulsive cavity potential. For weak pump the lasers favor a state with homogeneous density and predefined uniform spin direction. When one pump laser is polarized parallel to the cavity mode polarization, the photons coherently scattered into the resonator induce a polarization gradient along the cavity axis, which mediates long-range density-density, spin-density, and spin-spin interactions. We show that the coupled atom-cavity system implements central aspects of the $t$-$J$-$V$-$W$ model with a rich phase diagram. At the mean-field limit we identify at least four qualitatively distinct density- and spin-ordered phases including ferro- and anti-ferromagnetic order along the cavity axis, which can be controlled via the pump strength and detunings. Nondestructive observation of amplitude and phase of the emitted fields bears strong signatures of the realized phase and allows for real-time observation of the underlying dynamics.
{"title":"Spin and density self-ordering in dynamic polarization gradients fields","authors":"N. Masalaeva, W. Niedenzu, F. Mivehvar, H. Ritsch","doi":"10.1103/PHYSREVRESEARCH.3.013173","DOIUrl":"https://doi.org/10.1103/PHYSREVRESEARCH.3.013173","url":null,"abstract":"We study the zero-temperature quantum phase diagram for a two-component Bose-Einstein condensate in an optical cavity. The two atomic spin states are Raman coupled by two transverse orthogonally-polarized, blue detuned plane-wave lasers inducing a repulsive cavity potential. For weak pump the lasers favor a state with homogeneous density and predefined uniform spin direction. When one pump laser is polarized parallel to the cavity mode polarization, the photons coherently scattered into the resonator induce a polarization gradient along the cavity axis, which mediates long-range density-density, spin-density, and spin-spin interactions. We show that the coupled atom-cavity system implements central aspects of the $t$-$J$-$V$-$W$ model with a rich phase diagram. At the mean-field limit we identify at least four qualitatively distinct density- and spin-ordered phases including ferro- and anti-ferromagnetic order along the cavity axis, which can be controlled via the pump strength and detunings. Nondestructive observation of amplitude and phase of the emitted fields bears strong signatures of the realized phase and allows for real-time observation of the underlying dynamics.","PeriodicalId":8838,"journal":{"name":"arXiv: Quantum Gases","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72940591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-23DOI: 10.11606/t.76.2020.tde-29062020-150004
F. T. Sant'Ana
Bosonic atoms confined in optical lattices are described by the Bose-Hubbard model and can exist in two different phases, Mott insulator or superfluid, depending on the strength of the system parameters. In the vicinity of the phase boundary, there are degeneracies that occur between every two adjacent Mott lobes. Because of this, nondegenerate perturbation theory fails to give meaningful results for the condensate density: it predicts a phase transition in a point of the phase diagram where no transition occurs. Motivated by this, we develop two different degenerate perturbative methods to solve the degeneracy-related problems. Moreover, we study the one-dimensional repulsively interacting Bose gas under harmonic confinement, with special attention to the asymptotic behavior of the momentum distribution, which is a universal $k^{-4}$ decay characterized by the Tan's contact. The latter constitutes a direct signature of the short-range correlations in such an interacting system and provides valuable insights about the role of the interparticle interactions. We investigate the system constituted of $N$ interacting particles in the strongly interacting limit. In such a regime, the strong interparticle interaction makes the bosons behave similarly to the ideal Fermi gas. Because of the difficulty in analytically solving the system for $N$ particles at finite interaction, the Tonks-Girardeau regime provides a favorable scenario to probe the contact. Therefore, we are able to provide an analytical formula for the Tan's contact. Furthermore, we analyze the scaling properties of the Tan's contact in terms of $N$ in the high-temperature regime as well as in the strongly interacting regime. Finally, we compare our analytical calculations of the Tan's contact to quantum Monte Carlo simulations and discuss some fundamental differences between the canonical and the grand-canonical ensembles.
{"title":"A study on quantum gases: bosons in optical lattices and the one-dimensional interacting Bose gas","authors":"F. T. Sant'Ana","doi":"10.11606/t.76.2020.tde-29062020-150004","DOIUrl":"https://doi.org/10.11606/t.76.2020.tde-29062020-150004","url":null,"abstract":"Bosonic atoms confined in optical lattices are described by the Bose-Hubbard model and can exist in two different phases, Mott insulator or superfluid, depending on the strength of the system parameters. In the vicinity of the phase boundary, there are degeneracies that occur between every two adjacent Mott lobes. Because of this, nondegenerate perturbation theory fails to give meaningful results for the condensate density: it predicts a phase transition in a point of the phase diagram where no transition occurs. Motivated by this, we develop two different degenerate perturbative methods to solve the degeneracy-related problems. Moreover, we study the one-dimensional repulsively interacting Bose gas under harmonic confinement, with special attention to the asymptotic behavior of the momentum distribution, which is a universal $k^{-4}$ decay characterized by the Tan's contact. The latter constitutes a direct signature of the short-range correlations in such an interacting system and provides valuable insights about the role of the interparticle interactions. We investigate the system constituted of $N$ interacting particles in the strongly interacting limit. In such a regime, the strong interparticle interaction makes the bosons behave similarly to the ideal Fermi gas. Because of the difficulty in analytically solving the system for $N$ particles at finite interaction, the Tonks-Girardeau regime provides a favorable scenario to probe the contact. Therefore, we are able to provide an analytical formula for the Tan's contact. Furthermore, we analyze the scaling properties of the Tan's contact in terms of $N$ in the high-temperature regime as well as in the strongly interacting regime. Finally, we compare our analytical calculations of the Tan's contact to quantum Monte Carlo simulations and discuss some fundamental differences between the canonical and the grand-canonical ensembles.","PeriodicalId":8838,"journal":{"name":"arXiv: Quantum Gases","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91104893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-23DOI: 10.1103/physrevresearch.2.043065
I. Yatsuta, B. Malomed, A. Yakimenko
We propose emulation of Hawking radiation by means of acoustic excitations propagating on top of a persistent current in an atomic Bose-Einstein condensate loaded in an annular confining potential. The setting admits realization of sonic black and white event horizons. It is found that density-density correlations, representing the acoustic analogue of the Hawking radiation, are strongly affected by the perimeter of the ring-shaped configuration and number of discrete acoustic modes admitted by it. Remarkably, there is a minimum radius of the ring which admits the emulation of the Hawking radiation. We also discuss a possible similarity of properties of the matter-wave sonic black holes to the known puzzle of the stability of Planck-scale primordial black holes in quantum gravity.
{"title":"Acoustic analog of Hawking radiation in quantized circular superflows of Bose-Einstein condensates","authors":"I. Yatsuta, B. Malomed, A. Yakimenko","doi":"10.1103/physrevresearch.2.043065","DOIUrl":"https://doi.org/10.1103/physrevresearch.2.043065","url":null,"abstract":"We propose emulation of Hawking radiation by means of acoustic excitations propagating on top of a persistent current in an atomic Bose-Einstein condensate loaded in an annular confining potential. The setting admits realization of sonic black and white event horizons. It is found that density-density correlations, representing the acoustic analogue of the Hawking radiation, are strongly affected by the perimeter of the ring-shaped configuration and number of discrete acoustic modes admitted by it. Remarkably, there is a minimum radius of the ring which admits the emulation of the Hawking radiation. We also discuss a possible similarity of properties of the matter-wave sonic black holes to the known puzzle of the stability of Planck-scale primordial black holes in quantum gravity.","PeriodicalId":8838,"journal":{"name":"arXiv: Quantum Gases","volume":"84 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77897720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-23DOI: 10.1103/physrevresearch.2.033274
D. Colas
Self-accelerating beams are fascinating solutions of the Schrodinger equation. Thanks to their particular phase engineering, they can accelerate without the need of external potentials or applied forces. Finite-energy approximations of these beams have led to many applications, spanning from particle manipulation to robust in vivo imaging. The most studied and emblematic beam, the Airy beam, has been recently investigated in the context of the fractional Schrodinger equation. It was notably found that the packet acceleration would decrease with the reduction of the fractional order. Here, I study the case of a general nth-order self-accelerating caustic beam in the fractional Schrodinger equation. Using a Madelung decomposition combined with the wavelet transform, I derive the analytical expression of the beam's acceleration. I show that the non-accelerating limit is reached for infinite phase order or when the fractional order is reduced to 1. This work provides a quantitative description of self-accelerating caustic beams' properties.
{"title":"Self-accelerating beam dynamics in the space fractional Schrödinger equation","authors":"D. Colas","doi":"10.1103/physrevresearch.2.033274","DOIUrl":"https://doi.org/10.1103/physrevresearch.2.033274","url":null,"abstract":"Self-accelerating beams are fascinating solutions of the Schrodinger equation. Thanks to their particular phase engineering, they can accelerate without the need of external potentials or applied forces. Finite-energy approximations of these beams have led to many applications, spanning from particle manipulation to robust in vivo imaging. The most studied and emblematic beam, the Airy beam, has been recently investigated in the context of the fractional Schrodinger equation. It was notably found that the packet acceleration would decrease with the reduction of the fractional order. Here, I study the case of a general nth-order self-accelerating caustic beam in the fractional Schrodinger equation. Using a Madelung decomposition combined with the wavelet transform, I derive the analytical expression of the beam's acceleration. I show that the non-accelerating limit is reached for infinite phase order or when the fractional order is reduced to 1. This work provides a quantitative description of self-accelerating caustic beams' properties.","PeriodicalId":8838,"journal":{"name":"arXiv: Quantum Gases","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88516718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-21DOI: 10.1103/physreva.102.053320
Qing-Li Zhu, L. Pan, Jin An
We study the dynamics of a Rashba spin-orbit coupled spin-1 ferromagnetic Bose-Einstein condensate under a linear Zeeman magnetic field(ZF) disturbed by a moving obstacle. The Bogoliubov excitation spectrums and corresponding critical excitations in different situations are analyzed. The structure of the coreless vortex or antivortex generated by the moving obstacle has been investigated. When the ZF is applied along x direction, the vortex cores for the three components of a(an) vortex(antivortex) could be arranged into a vertical line, and their order would be reversed as the spin-orbit coupling increases. When the ZF is parallel to z direction, a skyrmion-like vortex ground state could be induced even by a static obstacle. This topological structure is also found to be dynamically stable if the obstacle is moving at a relatively small velocity.
{"title":"Spin-orbit-coupled spin-1 Bose-Einstein-condensate flow past an obstacle in the presence of a Zeeman field","authors":"Qing-Li Zhu, L. Pan, Jin An","doi":"10.1103/physreva.102.053320","DOIUrl":"https://doi.org/10.1103/physreva.102.053320","url":null,"abstract":"We study the dynamics of a Rashba spin-orbit coupled spin-1 ferromagnetic Bose-Einstein condensate under a linear Zeeman magnetic field(ZF) disturbed by a moving obstacle. The Bogoliubov excitation spectrums and corresponding critical excitations in different situations are analyzed. The structure of the coreless vortex or antivortex generated by the moving obstacle has been investigated. When the ZF is applied along x direction, the vortex cores for the three components of a(an) vortex(antivortex) could be arranged into a vertical line, and their order would be reversed as the spin-orbit coupling increases. When the ZF is parallel to z direction, a skyrmion-like vortex ground state could be induced even by a static obstacle. This topological structure is also found to be dynamically stable if the obstacle is moving at a relatively small velocity.","PeriodicalId":8838,"journal":{"name":"arXiv: Quantum Gases","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85604884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-14DOI: 10.1142/S0217732321500061
I. Arraut
We study the analogy between the Hawking radiation in Black-Holes and the Quantum depletion process of a Bose-Einstein condensate by using the Bogoliubov transformations method. We find that the relation between the Bogoliubov coefficients is similar in both cases (in the appropriate regimes). We then connect the condensate variables with those associated to the Black-Hole, demonstrating then that the zero temperature regime of the condensate is equivalent to the existence of an event horizon in gravity.
{"title":"Black-Hole evaporation and quantum-depletion in Bose–Einstein condensates","authors":"I. Arraut","doi":"10.1142/S0217732321500061","DOIUrl":"https://doi.org/10.1142/S0217732321500061","url":null,"abstract":"We study the analogy between the Hawking radiation in Black-Holes and the Quantum depletion process of a Bose-Einstein condensate by using the Bogoliubov transformations method. We find that the relation between the Bogoliubov coefficients is similar in both cases (in the appropriate regimes). We then connect the condensate variables with those associated to the Black-Hole, demonstrating then that the zero temperature regime of the condensate is equivalent to the existence of an event horizon in gravity.","PeriodicalId":8838,"journal":{"name":"arXiv: Quantum Gases","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85882326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-06-11DOI: 10.1103/physreva.102.043316
M. Momme, O. O. Prikhodko, Yuriy Bidasyuk
We present a detailed study of the spectrum and dispersion of Bogoliubov quasiparticles in two coupled elongated Bose-Einstein condensates. We develop an analytically solvable model that approximates two infinite homogeneous condensates and compare its predictions to a numerical simulation of a realistic trapped system. While the comparisons show a reasonable agreement between the two models, they also manifest the existence of several anomalous Bogoliubov modes in the spectrum. These modes show degeneracy in both energy and momentum together with self-localization in the coordinate space.
{"title":"Dispersion relations and self-localization of quasiparticles in coupled elongated Bose-Einstein condensates","authors":"M. Momme, O. O. Prikhodko, Yuriy Bidasyuk","doi":"10.1103/physreva.102.043316","DOIUrl":"https://doi.org/10.1103/physreva.102.043316","url":null,"abstract":"We present a detailed study of the spectrum and dispersion of Bogoliubov quasiparticles in two coupled elongated Bose-Einstein condensates. We develop an analytically solvable model that approximates two infinite homogeneous condensates and compare its predictions to a numerical simulation of a realistic trapped system. While the comparisons show a reasonable agreement between the two models, they also manifest the existence of several anomalous Bogoliubov modes in the spectrum. These modes show degeneracy in both energy and momentum together with self-localization in the coordinate space.","PeriodicalId":8838,"journal":{"name":"arXiv: Quantum Gases","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87519513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-05-25DOI: 10.1103/physreva.103.013303
Pei-Song He, Zhaoxin Liang
Exciton-polariton condensate in semiconductor microcavities constitute a novel kind of non-equilibrium superfluid. In a recent experiment [P. Stepanov, {it et. al.,} Nat. Commun. {bf 10}, 1038 (2019)], the dispersion relation of collective excitations in a polariton condensate under the resonant pumping has been investigated with the emphasis on the role of reservoir of long-lived excitons in determining the superfluidity. Inspired by such an experimental advance, we study the superfluidity of a exciton-polaritonn condensate under non-resonant pumping by calculating the drag force exerted on a classical impurity moving in a polariton condensate. For a non-resonant pumped polariton condensate prepared in the gapped phase, due to the reservoir's modes, the drag force can be large when the velocity of the impurity is small. Besides, as the velocity increases, the drag force can decrease. For not very large velocity, the drag force is enhanced if the condensate is tuned to be more dissipative. When the condensate is close to the transition point between the gapped phase and the gapless one, the drag force is similar to that of the equilibrium superfluid. Our present work reveals the effects of the reservoir's modes on the superfluidity properties of a polariton condensate with the non-resonant pumping.
{"title":"Drag force of an exciton-polariton condensate under nonresonant pumping","authors":"Pei-Song He, Zhaoxin Liang","doi":"10.1103/physreva.103.013303","DOIUrl":"https://doi.org/10.1103/physreva.103.013303","url":null,"abstract":"Exciton-polariton condensate in semiconductor microcavities constitute a novel kind of non-equilibrium superfluid. In a recent experiment [P. Stepanov, {it et. al.,} Nat. Commun. {bf 10}, 1038 (2019)], the dispersion relation of collective excitations in a polariton condensate under the resonant pumping has been investigated with the emphasis on the role of reservoir of long-lived excitons in determining the superfluidity. Inspired by such an experimental advance, we study the superfluidity of a exciton-polaritonn condensate under non-resonant pumping by calculating the drag force exerted on a classical impurity moving in a polariton condensate. For a non-resonant pumped polariton condensate prepared in the gapped phase, due to the reservoir's modes, the drag force can be large when the velocity of the impurity is small. Besides, as the velocity increases, the drag force can decrease. For not very large velocity, the drag force is enhanced if the condensate is tuned to be more dissipative. When the condensate is close to the transition point between the gapped phase and the gapless one, the drag force is similar to that of the equilibrium superfluid. Our present work reveals the effects of the reservoir's modes on the superfluidity properties of a polariton condensate with the non-resonant pumping.","PeriodicalId":8838,"journal":{"name":"arXiv: Quantum Gases","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90987625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：