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:1403.4823 · Physical Review A

Miscible-immiscible quantum phase transition in coupled two-component Bose-Einstein condensates in one-dimensional optical lattices

Fei Zhan, Jacopo Sabbatini, Matthew J. Davis, Ian P. McCulloch

Published Aug 26, 2014• 18 citations
arXivHTMLPDF

Abstract

We study the miscible-immiscible quantum phase transition in a linearly coupled binary Bose-Hubbard model in one dimension that can describe the low-energy properties of a two-component Bose-Einstein condensate in optical lattices. With the quantum many-body ground state obtained from the density matrix renormalization group algorithm, we calculate the characteristic physical quantities of the phase transition controlled by the linear coupling between the two components. Furthermore we calculate the Binder cumulant to determine the critical point and construct the phase diagram. The strong-coupling expansion shows that in the Mott insulator regime the model Hamiltonian can be mapped to a spin-$1/2$ $\mathit{XXZ}$ model with a transverse magnetic field.

DOI
10.1103/physreva.90.023630

Related papers

Magnetic phase transition in coherently coupled Bose gases in optical lattices

Luca Barbiero, Marta Abad, Alessio Recati

We describe the ground state of a gas of bosonic atoms with two coherently coupled internal levels in a deep optical lattice in a one-dimensional geometry. In the single-band approximation this system is described by a Bose-Hubbard Hamiltonian. The system has a superfluid and a Mott insulating phase that can be either paramagnetic or ferromagnetic. We characterize the quantum phase transitions at unit filling by means of a density-matrix renormalization-group technique and compare the results with a mean-field approach and an effective spin Hamiltonian. The presence of the ferromagnetic Ising-like transition modifies the Mott lobes. In the Mott insulating region the system maps to the ferromagnetic spin-1/2 $XXZ$ model in a transverse field and the numerical results compare very well with the analytical results obtained from the spin model. In the superfluid regime quantum fluctuations strongly modify the phase transition with respect to the well-established mean-field three-dimensional classical bifurcation.

arXiv:1403.4185•Physical Review A•Mar 25, 2016•11 citations

Symmetries and the miscible-immiscible transition in Bose–Einstein condensates confined in optical lattice

Shu-Song Wang, Suying Zhang

Abstract We present a systematic investigation of symmetries and ground state phase transitions in two-dimensional Bose–Einstein condensates with rotational and spin–orbit couplings confined within one-dimensional optical lattices. For lattice phases φ = π 2 , the vortex arrangement exhibits mirror symmetry about the y-axis, and the density distribution in momentum space maintains mirror symmetry about the k x -axis. For φ = 0, in contrast, the system exhibits spontaneous symmetry breaking, leading to ground state degeneracy. The optical lattice divides the condensate into distinct units. With a fixed spin–orbit coupling strength, the two-component condensates in different units successively undergo immiscible to miscible transitions as the rotational angular frequency increases. For φ = 0, in particular, the unit of condensate located in the center of the external potential consistently remains in the phase separation.

Physica Scripta•Nov 1, 2025•0 citations

Transition to miscibility in a binary Bose–Einstein condensate induced by linear coupling

Ilya M. Merhasin, Boris A. Malomed, Rodislav Driben

A one-dimensional mean-field model of a two-component condensate in the parabolic trap is considered, with the components corresponding to different spin states of the same atom. We demonstrate that the linear coupling (interconversion) between them, induced by a resonant electromagnetic wave, can drive the immiscible binary condensate into a miscible state. This transition is predicted in an analytical form by means of a variational approximation (for an infinitely long system), and is confirmed by direct numerical solutions of the symmetric and asymmetric models (the asymmetry accounts for a possible difference in the chemical potential between the components). We define an order parameter of the system as an off-centre shift of the centre of mass of each component. A numerically found dependence of the order parameter on the linear-coupling strength reveals a second-kind phase transition (in an effectively finite system). The phase transition looks very similar in two different regimes, namely, with a fixed number of atoms, or a fixed chemical potential. An additional transition is possible between double- and single-humped density distributions in the weak component of a strongly asymmetric system. We also briefly consider dynamical states, with the two components oscillating relative to each other. In this case, the components periodically separate even if they should be mixed in the static configuration.

Journal of Physics B Atomic Molecular and Optical Physics•Mar 16, 2005•95 citations

Miscibility-immiscibility transition of strongly interacting bosonic mixtures in optical lattices

Rukmani Bai, Soumik Bandyopadhyay

Interaction plays a key role in the mixing properties of a multicomponent system. The miscibility-immiscibility transition (MIT) in a weakly interacting mixture of Bose gases is predominantly determined by the strengths of the intra- and intercomponent two-body contact interactions. However, in the strongly interacting regime interaction-induced processes become relevant. Despite previous studies on bosonic mixtures in optical lattices, the effects of the interaction-induced processes on the MIT remains unexplored. In this work, we investigate the MIT in the strongly interacting phases of two-component bosonic mixture trapped in a homogeneous two-dimensional square optical lattice. Particularly we examine the MIT condition when both the components are in superfluid, one-body staggered superfluid, or supersolid phases. Our study uncovers that MIT condition is significantly shaped by the interplay of competing nonlocal intra- and intercomponent density-induced tunneling effects, as well as off-site interactions. Notably, we demonstrate that the MIT condition for the staggered superfluid phase exhibits an inequality that is inverted compared to the conventional MIT condition associated with superfluid or supersolid phases driven by local contact interactions. In addition, we present the phase diagram of the Bose-Hubbard model incorporating nonlocal processes, derived using a site-decoupling mean-field approach with the Gutzwiller ansatz. Our study contributes to the better understanding of miscibility properties of multicomponent systems in the strongly interacting regime.

arXiv:2403.14601•Physical Review A•Jul 25, 2025•0 citations

Interference of Atomic Levels and Superfluid-Mott Insulator Phase Transitions in a Two-Component Bose-Einstein Condensate

Konstantin V. Krutitsky, R. Graham

The superfluid-Mott insulator phase transition in a Bose-Einstein condensate of neutral atoms with doubly degenerate internal ground states in an optical lattice is theoretically investigated. The optical lattice is created by two counterpropagating linearly polarized laser beams with the angle theta between the polarization vectors (lin-angle-lin configuration). The phase diagram of the system and the critical values of the parameters are worked out. It is shown that the sign of the detuning plays an important role and that there is a strong suppression of the Mott transition in the case of blue detuning. Varying the laser intensity and/or the angle theta one can manipulate the Mott insulator to superfluid quantum phase transition as well as prepare the condensate in physically distinguishable "ferromagnetic" and "antiferromagnetic" superfluid states.

arXiv:cond-mat/0307287•Physical Review Letters•Dec 11, 2003•22 citations

Quantum phase transition in a multicomponent Bose-Einstein condensate in optical lattices

Guang‐Hong Chen, Yong-Shi Wu

We present a general lattice model for a multicomponent atomic Bose-Einstein system in an optical lattice. Using the model, we analytically study the quantum phase transition between the Mott insulator and a superfluid. A mean-field theory is developed from the Mott-insulator ground state. When the interspecies interactions are strong enough, the Mott insulator demonstrates the phase separation behavior. For weak interspecies interactions, the multispecies system is miscible. Finally, the phase diagram is discussed with emphasis on the role of interspecies interactions. The tip and the shape of the Mott insulator lobes do not depend on the interspecies interactions, but the latter indeed modify the position of the phase boundaries.

arXiv:cond-mat/0205440•Physical Review A•Jan 22, 2003•76 citations
We study the miscible-immiscible quantum phase transition in a linearly coupled binary Bose-Hubbard model in one dimension that can describe the low-energy properties of a two-component Bose-Einstein condensate in optical lattices. With the quantum many-body ground state obtained from the density matrix renormalization group algorithm, we calculate the characteristic physical quantities of the phase transition controlled by the linear coupling between the two components. Furthermore we calculate the Binder cumulant to determine the critical point and construct the phase diagram. The strong-coupling expansion shows that in the Mott insulator regime the model Hamiltonian can be mapped to a spin-1/21/21/2 XXZ\mathit{XXZ}XXZ model with a transverse magnetic field.
We describe the ground state of a gas of bosonic atoms with two coherently coupled internal levels in a deep optical lattice in a one-dimensional geometry. In the single-band approximation this system is described by a Bose-Hubbard Hamiltonian. The system has a superfluid and a Mott insulating phase that can be either paramagnetic or ferromagnetic. We characterize the quantum phase transitions at unit filling by means of a density-matrix renormalization-group technique and compare the results with a mean-field approach and an effective spin Hamiltonian. The presence of the ferromagnetic Ising-like transition modifies the Mott lobes. In the Mott insulating region the system maps to the ferromagnetic spin-1/2 XXZXXZXXZ model in a transverse field and the numerical results compare very well with the analytical results obtained from the spin model. In the superfluid regime quantum fluctuations strongly modify the phase transition with respect to the well-established mean-field three-dimensional classical bifurcation.
Abstract We present a systematic investigation of symmetries and ground state phase transitions in two-dimensional Bose–Einstein condensates with rotational and spin–orbit couplings confined within one-dimensional optical lattices. For lattice phases φ = π 2 , the vortex arrangement exhibits mirror symmetry about the y-axis, and the density distribution in momentum space maintains mirror symmetry about the k x -axis. For φ = 0, in contrast, the system exhibits spontaneous symmetry breaking, leading to ground state degeneracy. The optical lattice divides the condensate into distinct units. With a fixed spin–orbit coupling strength, the two-component condensates in different units successively undergo immiscible to miscible transitions as the rotational angular frequency increases. For φ = 0, in particular, the unit of condensate located in the center of the external potential consistently remains in the phase separation.
A one-dimensional mean-field model of a two-component condensate in the parabolic trap is considered, with the components corresponding to different spin states of the same atom. We demonstrate that the linear coupling (interconversion) between them, induced by a resonant electromagnetic wave, can drive the immiscible binary condensate into a miscible state. This transition is predicted in an analytical form by means of a variational approximation (for an infinitely long system), and is confirmed by direct numerical solutions of the symmetric and asymmetric models (the asymmetry accounts for a possible difference in the chemical potential between the components). We define an order parameter of the system as an off-centre shift of the centre of mass of each component. A numerically found dependence of the order parameter on the linear-coupling strength reveals a second-kind phase transition (in an effectively finite system). The phase transition looks very similar in two different regimes, namely, with a fixed number of atoms, or a fixed chemical potential. An additional transition is possible between double- and single-humped density distributions in the weak component of a strongly asymmetric system. We also briefly consider dynamical states, with the two components oscillating relative to each other. In this case, the components periodically separate even if they should be mixed in the static configuration.
Interaction plays a key role in the mixing properties of a multicomponent system. The miscibility-immiscibility transition (MIT) in a weakly interacting mixture of Bose gases is predominantly determined by the strengths of the intra- and intercomponent two-body contact interactions. However, in the strongly interacting regime interaction-induced processes become relevant. Despite previous studies on bosonic mixtures in optical lattices, the effects of the interaction-induced processes on the MIT remains unexplored. In this work, we investigate the MIT in the strongly interacting phases of two-component bosonic mixture trapped in a homogeneous two-dimensional square optical lattice. Particularly we examine the MIT condition when both the components are in superfluid, one-body staggered superfluid, or supersolid phases. Our study uncovers that MIT condition is significantly shaped by the interplay of competing nonlocal intra- and intercomponent density-induced tunneling effects, as well as off-site interactions. Notably, we demonstrate that the MIT condition for the staggered superfluid phase exhibits an inequality that is inverted compared to the conventional MIT condition associated with superfluid or supersolid phases driven by local contact interactions. In addition, we present the phase diagram of the Bose-Hubbard model incorporating nonlocal processes, derived using a site-decoupling mean-field approach with the Gutzwiller ansatz. Our study contributes to the better understanding of miscibility properties of multicomponent systems in the strongly interacting regime.
The superfluid-Mott insulator phase transition in a Bose-Einstein condensate of neutral atoms with doubly degenerate internal ground states in an optical lattice is theoretically investigated. The optical lattice is created by two counterpropagating linearly polarized laser beams with the angle theta between the polarization vectors (lin-angle-lin configuration). The phase diagram of the system and the critical values of the parameters are worked out. It is shown that the sign of the detuning plays an important role and that there is a strong suppression of the Mott transition in the case of blue detuning. Varying the laser intensity and/or the angle theta one can manipulate the Mott insulator to superfluid quantum phase transition as well as prepare the condensate in physically distinguishable "ferromagnetic" and "antiferromagnetic" superfluid states.
We present a general lattice model for a multicomponent atomic Bose-Einstein system in an optical lattice. Using the model, we analytically study the quantum phase transition between the Mott insulator and a superfluid. A mean-field theory is developed from the Mott-insulator ground state. When the interspecies interactions are strong enough, the Mott insulator demonstrates the phase separation behavior. For weak interspecies interactions, the multispecies system is miscible. Finally, the phase diagram is discussed with emphasis on the role of interspecies interactions. The tip and the shape of the Mott insulator lobes do not depend on the interspecies interactions, but the latter indeed modify the position of the phase boundaries.