Quantum and thermal fluctuations in two-component Bose gases

Abstract

We study the effects of quantum and thermal fluctuations on Bose-Bose mixtures at finite temperature employing the time-dependent Hartree-Fock-Bogoliubov (TDHFB) theory. The theory governs selfconsistently the motion of the condensates, the noncondensates and of the anomalous components on an equal footing. The finite temperature criterion for the phase separation is established. We numerically analyze the temperature dependence of different densities for both miscible and immiscible mixtures. We show that the degree of the overlap between the two condensates and the thermal clouds is lowered and the relative motion of the centers-of-mass of the condensed and thermal components is strongly damped due to the presence of the pair anomalous fluctuations. Our results are compared with previous theoretical and experimental findings. On the other hand, starting from our TDHFB equations, we develop a random-phase theory for the elementary excitations in a homogeneous mixture. We find that the normal and anomalous fluctuations may lead to enhance the excitations and the thermodynamics of the system.

10 pages, 5 figures

References in corpus (17)

• Quantum liquid droplets in a mixture of Bose-Einstein condensates
• Quantum-fluctuation-driven crossover from a dilute Bose-Einstein condensate to a macro-droplet in a dipolar quantum fluid
• Creation of ultracold ${}^{87}$RbCs molecules in the rovibrational ground state
• Double species condensate with tunable interspecies interactions
• Dual-Species Bose-Einstein Condensate of ${}^{87}$Rb and ${}^{133}$Cs
• Observation of heteronuclear atomic Efimov resonances
• Tuning of heteronuclear interactions in a quantum-degenerate Fermi-Bose mixture
• Control of the interaction in a Fermi-Bose mixture
• Production of a dual-species Bose-Einstein condensate of Rb and Cs atoms
• Representative statistical ensembles for Bose systems with broken gauge symmetry
• Self-localized state and solitons in a Bose-Einstein-condensate-impurity mixture at finite temperature
• Collective oscillations of a confined Bose gas at finite temperature in the random-phase approximation
• Variational self-consistent theory for trapped Bose gases at finite temperature
• Large-N approximation for single- and two-component dilute Bose gases
• Kinetic Model of Trapped Finite Temperature Binary Condensates
• Non-equilibrium Atomic Condensates and Mixtures: Collective Modes, Condensate Growth and Thermalization
• Collective excitations of a dilute Bose gas at finite temperature: TDHFB Theory

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