Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:cond-mat/0512522 · Journal of Physics B Atomic Molecular and Optical Physics

Avoided level-crossing, correlation and entanglement of two-component Bose–Einstein condensates in a double well

Weibin Li, Wen‐Xing Yang, Xiao-Tao Xie, Jiahua Li, Xiaoxue Yang

Published Jul 11, 2006• 5 citations
arXivHTMLPDF

Abstract

We consider a novel system of two-component atomic Bose-Einstein condensate in a double-well potential. Based on the well-known two-mode approximation, we demonstrate that there are obvious avoided level-crossings when both interspecies and intraspecies interactions of two species are increased. The quantum dynamics of the system exhibits revised oscillating behaviors compared with a single component condensate. We also examine the entanglement of two species. Our numerical calculations show the onset of entanglement can be signed as a violation of Cauchy-Schwarz inequality of second-order cross correlation function. Consequently, we use Von Neumann entropy to quantity the degree of entanglement.

DOI
10.1088/0953-4075/39/14/016

Related papers

Two-mode entanglement in two-component Bose-Einstein condensates

H. T. Ng, P. T. Leung

We study the generation of two-mode entanglement in a two-component Bose-Einstein condensate trapped in a double-well potential. The dynamics of the system is shown to be equivalent to that of two coupled harmonic oscillators in the low excitation regime. Strong entanglement between the two components can be achieved if the interspecies interaction is sufficiently strong. In particular, the condensate constitutes a symmetric Gaussian system and hence its entanglement of formation can be measured directly by fluctuations in the quadratures of the two constituent components.

arXiv:quant-ph/0405117•Physical Review A•Jan 3, 2005•32 citations

Entanglement and entropy production in coupled single-mode Bose-Einstein condensates

Izabella Lovas, József Fortágh, Eugene Demler +1 more

We investigate the time evolution of the entanglement entropy of coupled single-mode Bose-Einstein condensates in a double-well potential at $T=0$ temperature by combining numerical results with analytical approximations. We find that the coherent oscillations of the condensates result in entropy oscillations on the top of a linear entropy generation at short time scales. Due to dephasing, the entropy eventually saturates to a stationary value, in spite of the lack of equilibration. We show that this long-time limit of the entropy reflects the semiclassical dynamics of the system, revealing the self-trapping phase transition of the condensates at large interaction strength by a sudden entropy jump. We compare the stationary limit of the entropy to the prediction of a classical microcanonical ensemble and find surprisingly good agreement in spite of the nonequilibrium state of the system. Our predictions should be experimentally observable on a Bose-Einstein condensate in a double-well potential or on a two-component condensate with interstate coupling.

arXiv:1706.04571•Physical Review A•Aug 17, 2017•7 citations

Quantum properties of a binary bosonic mixture in a double well

Pere Mujal, Bruno Juliá-Díaz, A. Polls

This work contains a detailed analysis of the properties of the ground state of a two-component two-site Bose-Hubbard model, which captures the physics of a binary mixture of Bose-Einstein condensates trapped in a double-well potential. The atom-atom interactions within each species and among the two species are taken as variable parameters, while the hopping terms are kept fixed. To characterize the ground state, we use observables such as the imbalance of population and its quantum uncertainty. The quantum many-body correlations present in the system are further quantified by studying the degree of condensation of each species, the entanglement between the two sites, and the entanglement between the two species. The latter is measured by means of the Schmidt gap, the von Neumann entropy, or the purity obtained after tracing out a part of the system. A number of relevant states are identified, e.g., Schr\"odinger catlike many-body states, in which the outcome of the population imbalance of both components is completely correlated, and other states with even larger von Neumann entropy which have a large spread in Fock space.

arXiv:1602.01339•Physical Review A•Apr 21, 2016•17 citations

Generation of Bell states in two-component Bose–Einstein condensates

Zhang Guo-Feng, Yin Wen, Liang Jiu-Qing +1 more

We examine analytically the generation of Bell state in Bose condensates of two interacting species trapped in a double well configuration. The density of probability for finding the entangled Bell state is given. The effect of the tunnelling rate and the interspecies interaction strength on the generation of Bell state is discussed. We find that the oscillation amplitude of the density of probability for finding the entangled Bell state becomes greater as the tunnelling rate Ω increases and the self-interaction strength of the component A(B) has no effect on it.

Chinese Physics•Jun 30, 2004•11 citations

Self-Trapping and Dynamical Stability of Two-Component Bose–Einstein Condensates in a Double-Well Potential

Wei Wang

The dynamics of two-component Bose–Einstein condensates (BECs) in a double-well potential is studied here. Interspecies (or component–component) couplings are taken into account. As a consequence of the couplings, more fixed points may appear in the BECs. We analyze the stability of the system around some special fixed points that are independent of the couplings. A critical interspecies coupling constant below which fixed points are stable is presented and analyzed. Numerical simulation of the dynamics of the two-component BECs is also presented and discussed.

Journal of the Physical Society of Japan•Aug 28, 2009•6 citations

Dynamics of a two-species Bose-Einstein condensate in a double well

Baoqing Sun, M. S. Pindzola

We study the dynamics of a two-species Bose-Einstein condensate in a double well. Such a system is characterized by the intraspecies and interspecies $s$-wave scattering as well as the Josephson tunneling between the two wells and the population transfer between the two species. We investigate the dynamics for some interesting regimes and present numerical results to support our conclusions. In the case of vanishing intraspecies scattering lengths and a weak interspecies scattering length, we find collapses and revivals in the population dynamics. A possible experimental implementation of our proposal is briefly discussed.

arXiv:0910.1773•Physical Review A•Sep 17, 2009•25 citations
We consider a novel system of two-component atomic Bose-Einstein condensate in a double-well potential. Based on the well-known two-mode approximation, we demonstrate that there are obvious avoided level-crossings when both interspecies and intraspecies interactions of two species are increased. The quantum dynamics of the system exhibits revised oscillating behaviors compared with a single component condensate. We also examine the entanglement of two species. Our numerical calculations show the onset of entanglement can be signed as a violation of Cauchy-Schwarz inequality of second-order cross correlation function. Consequently, we use Von Neumann entropy to quantity the degree of entanglement.
We study the generation of two-mode entanglement in a two-component Bose-Einstein condensate trapped in a double-well potential. The dynamics of the system is shown to be equivalent to that of two coupled harmonic oscillators in the low excitation regime. Strong entanglement between the two components can be achieved if the interspecies interaction is sufficiently strong. In particular, the condensate constitutes a symmetric Gaussian system and hence its entanglement of formation can be measured directly by fluctuations in the quadratures of the two constituent components.
We investigate the time evolution of the entanglement entropy of coupled single-mode Bose-Einstein condensates in a double-well potential at T=0T=0T=0 temperature by combining numerical results with analytical approximations. We find that the coherent oscillations of the condensates result in entropy oscillations on the top of a linear entropy generation at short time scales. Due to dephasing, the entropy eventually saturates to a stationary value, in spite of the lack of equilibration. We show that this long-time limit of the entropy reflects the semiclassical dynamics of the system, revealing the self-trapping phase transition of the condensates at large interaction strength by a sudden entropy jump. We compare the stationary limit of the entropy to the prediction of a classical microcanonical ensemble and find surprisingly good agreement in spite of the nonequilibrium state of the system. Our predictions should be experimentally observable on a Bose-Einstein condensate in a double-well potential or on a two-component condensate with interstate coupling.
This work contains a detailed analysis of the properties of the ground state of a two-component two-site Bose-Hubbard model, which captures the physics of a binary mixture of Bose-Einstein condensates trapped in a double-well potential. The atom-atom interactions within each species and among the two species are taken as variable parameters, while the hopping terms are kept fixed. To characterize the ground state, we use observables such as the imbalance of population and its quantum uncertainty. The quantum many-body correlations present in the system are further quantified by studying the degree of condensation of each species, the entanglement between the two sites, and the entanglement between the two species. The latter is measured by means of the Schmidt gap, the von Neumann entropy, or the purity obtained after tracing out a part of the system. A number of relevant states are identified, e.g., Schr\"odinger catlike many-body states, in which the outcome of the population imbalance of both components is completely correlated, and other states with even larger von Neumann entropy which have a large spread in Fock space.
We examine analytically the generation of Bell state in Bose condensates of two interacting species trapped in a double well configuration. The density of probability for finding the entangled Bell state is given. The effect of the tunnelling rate and the interspecies interaction strength on the generation of Bell state is discussed. We find that the oscillation amplitude of the density of probability for finding the entangled Bell state becomes greater as the tunnelling rate Ω increases and the self-interaction strength of the component A(B) has no effect on it.
The dynamics of two-component Bose–Einstein condensates (BECs) in a double-well potential is studied here. Interspecies (or component–component) couplings are taken into account. As a consequence of the couplings, more fixed points may appear in the BECs. We analyze the stability of the system around some special fixed points that are independent of the couplings. A critical interspecies coupling constant below which fixed points are stable is presented and analyzed. Numerical simulation of the dynamics of the two-component BECs is also presented and discussed.
We study the dynamics of a two-species Bose-Einstein condensate in a double well. Such a system is characterized by the intraspecies and interspecies sss-wave scattering as well as the Josephson tunneling between the two wells and the population transfer between the two species. We investigate the dynamics for some interesting regimes and present numerical results to support our conclusions. In the case of vanishing intraspecies scattering lengths and a weak interspecies scattering length, we find collapses and revivals in the population dynamics. A possible experimental implementation of our proposal is briefly discussed.