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

Journal of Physics B Atomic Molecular and Optical Physics

The quantum coherence of disordered dipolar bosonic gas

Ji-Guo Wang, Ai‐Xia Zhang, Rong-An Tang, Ji-Min Gao, Ju-Kui Xue

Published Apr 16, 2013• 2 citations
Publisher

Abstract

We investigate the coherence of correlated dipolar gas in the presence of disorder within a three-site Bose–Hubbard model. We show that the interplay between the on-site interaction, the inter-site dipole–dipole interactions (DDI) and the disorder exhibits new and interesting coherence characters that cannot take place in a non-dipolar system. The ratio between the on-site interaction and DDI plays a dominant role in the phase coherence. The resonance character of the coherence against both disorder and interactions emerges. DDI can enhance the coherence at certain values of the disorder and on-site interaction. In the coherence region, the enhancement of the coherence by disorder in a dipolar system is more significant than that in a non-dipolar system. In particular, the on-site interaction and DDI together can enhance the coherence even in the clean dipolar system (i.e. a dipolar system without disorder). However, without the on-site interaction, disorder, DDI or both together suppress the coherence. Furthermore, the relationship between the coherence and the energy gap and the compressibility of the system is also discussed.

DOI
10.1088/0953-4075/46/9/095301

Related papers

The coherence of boson–fermion mixed system

Ji-Guo Wang, Ju-Kui Xue

In this paper, we investigate the quantum coherence of Bose–Fermi mixtures of ultracold dipolar particles trapped in a three-site Bose–Fermi–Hubbard model. We show that the interplay between the boson–boson on-site interaction, boson–fermion on-site interaction, and boson–fermion inter-site dipole–dipole interaction (DDI) results in interesting coherence characters. When boson–boson on-site interaction is present, the resonance character of coherence against both boson–fermion DDI and boson–fermion on-site interaction emerges, the coherence of the system can be enhanced at certain values of boson–fermion on-site interaction and boson–fermion DDI. DDI of fermion–fermion affects the coherence weak and the phase coherence decreases monotonically for all the values of fermion–fermion DDI. The obtained coherent characters are further confirmed within the variational analyzing of the ground state energy.

Modern Physics Letters B•Feb 25, 2014•0 citations

Coherence of Disordered Bosonic Gas with Two- and Three-Body Interactions

Xin Zhang, Zi-Fa Yu, Ju-Kui Xue

We theoretically and numerically investigate the coherence of disordered bosonic gas with effective two- and three-body interactions within a two-site Bose–Hubbard model. By properly adjusting the two- and three-body interactions and the disorder, the coherence of the system exhibits new and interesting phenomena, including the resonance character of coherence against the disorder in the purely two- or three-body interactions system. More interestingly, the disorder and three-body interactions together can suppress the coherence of the purely three-body interactions system, which is different from the case in which the disorder and two-body interactions together can enhance the coherence in certain values of two-body interaction. Furthermore, when two- or three-body interactions are attractive or repulsive, the phase coherence exhibits completely different phenomena. In particular, if two- or three-body interactions are attractive, the coherence of the system can be significantly enhanced in certain regions. Correspondingly, the phase coherence of the system is strongly related to the effective interaction energy. The results provide a possible way for studying the coherence of bosonic gas with multi-atoms' interactions in the presence of the disorder.

Chinese Physics Letters•Apr 1, 2016•1 citation

Tunneling Dynamics of Dipolar Bosonic System with Periodically Modulated s -wave Scattering

Zi-Fa Yu, Ju-Kui Xue

Within the mean-field three-site Bose—Hubbard model, the tunneling dynamics of dipolar bosonic gas with a periodically modulation of s-wave scattering is investigated. The system experiences complex and rich coherent tunneling (CT)-coherent destruction of tunneling (CDT) transitions resulting from the correlated effect among the next-neighbor dipole-dipole interaction, the on-site interaction and the modulated s-wave scattering. In particular, The region of the modulated s-wave scattering for generating CT (CDT) is the widest (narrowest) when the on-site interaction and the next-neighbor dipole-dipole interaction have some correlated values, which are closely related to the tunneling energy and the interaction energy of the system. The correlated values for appearing CDT can be theoretically gained from the tunneling energy and the interaction energy of the system.

Communications in Theoretical Physics•May 1, 2014•0 citations

Equilibrium phases of dipolar lattice bosons in the presence of random diagonal disorder

C. Zhang, Arghavan Safavi-Naini, Barbara Capogrosso-Sansone

Ultracold gases offer an unprecedented opportunity to engineer disorder and interactions in a controlled manner. In an effort to understand the interplay between disorder, dipolar interactions, and quantum degeneracy, we study two-dimensional hard-core dipolar lattice bosons in the presence of on-site bound disorder. Our results are based on large-scale path-integral quantum Monte Carlo simulations by the worm algorithm. We study the ground-state phase diagram at a fixed half-integer filling factor for which the clean system is either a superfluid at a lower dipolar interaction strength or a checkerboard solid at a larger dipolar interaction strength. We find that, even for weak dipolar interactions, superfluidity is destroyed in favor of a Bose glass at a relatively low disorder strength. Interestingly, in the presence of disorder, superfluidity persists for values of the dipolar interaction strength for which the clean system is a checkerboard solid. At a fixed disorder strength, as the dipolar interaction is increased, superfluidity is destroyed in favor of a Bose glass. As the interaction is further increased, the system eventually develops extended checkerboard patterns in the density distribution. Due to the presence of disorder, though, grain boundaries and defects, responsible for a finite residual compressibility, are present in the density distribution. Finally, we study the robustness of the superfluid phase against thermal fluctuations.

arXiv:1711.04879•Physical Review A•Jan 16, 2018•8 citations

Coherent Destruction of Tunneling of Dipolar Bosonic Gas

Zi-Fa Yu, Ai‐Xia Zhang, Ju-Kui Xue

The tunneling dynamics of a dipolar bosonic gas with repulsive interactions in a periodically driven triple-well are investigated. Because of the coupled effect of long-range dipole-dipole interaction and the short-range of on-site interaction, the increase of the repulsive atomic interactions can either suppress tunneling or enhance tunneling and, thus, the system experiences rich coherent tunneling(CT)-coherent destruction of tunneling (CDT) transitions. In particular, as the repulsive atomic interactions increase, the system can undergo CT-CDT-CT-CDT or CDT-CT-CDT-CT-CDT transitions. This cannot occur in non-dipolar gas, where the increase of the repulsive atomic interaction only suppress tunneling and the system can only undergo CT-CDT transition. We further present a good understanding of the results with the help of the quasi-energy spectrum of the system.

Chinese Physics Letters•Jan 1, 2014•0 citations

Role of anisotropy in dipolar bosons in triple-well potentials

Albert Gallemí, M. Guilleumas, R. Mayol +1 more

Mesoscopic samples of polarized dipolar atoms confined in three spatially separated traps conform an extended Bose-Hubbard Hamiltonian in which different quantum phases appear depending on the competition between tunneling, on-site, and long-range intersite dipole-dipole interactions. Here, by choosing an appropriate configuration of triple wells, we analyze the role played by the anisotropic character inherent to the dipolar interaction in the phase diagram of the system. We further characterize the different phases as well as their boundaries by means of their entanglement properties.

arXiv:1311.4426•Physical Review A•Dec 30, 2013•31 citations
We investigate the coherence of correlated dipolar gas in the presence of disorder within a three-site Bose–Hubbard model. We show that the interplay between the on-site interaction, the inter-site dipole–dipole interactions (DDI) and the disorder exhibits new and interesting coherence characters that cannot take place in a non-dipolar system. The ratio between the on-site interaction and DDI plays a dominant role in the phase coherence. The resonance character of the coherence against both disorder and interactions emerges. DDI can enhance the coherence at certain values of the disorder and on-site interaction. In the coherence region, the enhancement of the coherence by disorder in a dipolar system is more significant than that in a non-dipolar system. In particular, the on-site interaction and DDI together can enhance the coherence even in the clean dipolar system (i.e. a dipolar system without disorder). However, without the on-site interaction, disorder, DDI or both together suppress the coherence. Furthermore, the relationship between the coherence and the energy gap and the compressibility of the system is also discussed.
In this paper, we investigate the quantum coherence of Bose–Fermi mixtures of ultracold dipolar particles trapped in a three-site Bose–Fermi–Hubbard model. We show that the interplay between the boson–boson on-site interaction, boson–fermion on-site interaction, and boson–fermion inter-site dipole–dipole interaction (DDI) results in interesting coherence characters. When boson–boson on-site interaction is present, the resonance character of coherence against both boson–fermion DDI and boson–fermion on-site interaction emerges, the coherence of the system can be enhanced at certain values of boson–fermion on-site interaction and boson–fermion DDI. DDI of fermion–fermion affects the coherence weak and the phase coherence decreases monotonically for all the values of fermion–fermion DDI. The obtained coherent characters are further confirmed within the variational analyzing of the ground state energy.
We theoretically and numerically investigate the coherence of disordered bosonic gas with effective two- and three-body interactions within a two-site Bose–Hubbard model. By properly adjusting the two- and three-body interactions and the disorder, the coherence of the system exhibits new and interesting phenomena, including the resonance character of coherence against the disorder in the purely two- or three-body interactions system. More interestingly, the disorder and three-body interactions together can suppress the coherence of the purely three-body interactions system, which is different from the case in which the disorder and two-body interactions together can enhance the coherence in certain values of two-body interaction. Furthermore, when two- or three-body interactions are attractive or repulsive, the phase coherence exhibits completely different phenomena. In particular, if two- or three-body interactions are attractive, the coherence of the system can be significantly enhanced in certain regions. Correspondingly, the phase coherence of the system is strongly related to the effective interaction energy. The results provide a possible way for studying the coherence of bosonic gas with multi-atoms' interactions in the presence of the disorder.
Within the mean-field three-site Bose—Hubbard model, the tunneling dynamics of dipolar bosonic gas with a periodically modulation of s-wave scattering is investigated. The system experiences complex and rich coherent tunneling (CT)-coherent destruction of tunneling (CDT) transitions resulting from the correlated effect among the next-neighbor dipole-dipole interaction, the on-site interaction and the modulated s-wave scattering. In particular, The region of the modulated s-wave scattering for generating CT (CDT) is the widest (narrowest) when the on-site interaction and the next-neighbor dipole-dipole interaction have some correlated values, which are closely related to the tunneling energy and the interaction energy of the system. The correlated values for appearing CDT can be theoretically gained from the tunneling energy and the interaction energy of the system.
Ultracold gases offer an unprecedented opportunity to engineer disorder and interactions in a controlled manner. In an effort to understand the interplay between disorder, dipolar interactions, and quantum degeneracy, we study two-dimensional hard-core dipolar lattice bosons in the presence of on-site bound disorder. Our results are based on large-scale path-integral quantum Monte Carlo simulations by the worm algorithm. We study the ground-state phase diagram at a fixed half-integer filling factor for which the clean system is either a superfluid at a lower dipolar interaction strength or a checkerboard solid at a larger dipolar interaction strength. We find that, even for weak dipolar interactions, superfluidity is destroyed in favor of a Bose glass at a relatively low disorder strength. Interestingly, in the presence of disorder, superfluidity persists for values of the dipolar interaction strength for which the clean system is a checkerboard solid. At a fixed disorder strength, as the dipolar interaction is increased, superfluidity is destroyed in favor of a Bose glass. As the interaction is further increased, the system eventually develops extended checkerboard patterns in the density distribution. Due to the presence of disorder, though, grain boundaries and defects, responsible for a finite residual compressibility, are present in the density distribution. Finally, we study the robustness of the superfluid phase against thermal fluctuations.
The tunneling dynamics of a dipolar bosonic gas with repulsive interactions in a periodically driven triple-well are investigated. Because of the coupled effect of long-range dipole-dipole interaction and the short-range of on-site interaction, the increase of the repulsive atomic interactions can either suppress tunneling or enhance tunneling and, thus, the system experiences rich coherent tunneling(CT)-coherent destruction of tunneling (CDT) transitions. In particular, as the repulsive atomic interactions increase, the system can undergo CT-CDT-CT-CDT or CDT-CT-CDT-CT-CDT transitions. This cannot occur in non-dipolar gas, where the increase of the repulsive atomic interaction only suppress tunneling and the system can only undergo CT-CDT transition. We further present a good understanding of the results with the help of the quasi-energy spectrum of the system.
Mesoscopic samples of polarized dipolar atoms confined in three spatially separated traps conform an extended Bose-Hubbard Hamiltonian in which different quantum phases appear depending on the competition between tunneling, on-site, and long-range intersite dipole-dipole interactions. Here, by choosing an appropriate configuration of triple wells, we analyze the role played by the anisotropic character inherent to the dipolar interaction in the phase diagram of the system. We further characterize the different phases as well as their boundaries by means of their entanglement properties.