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:0807.5110 · Physical Review A

Thomas-Fermi versus one- and two-dimensional regimes of a trapped dipolar Bose-Einstein condensate

Nicholas G. Parker, Duncan H J O’Dell

Published Oct 21, 2008• 50 citations
arXivHTMLPDF

Abstract

We derive the criteria for the Thomas-Fermi regime of a dipolar Bose-Einstein condensate in cigar-shaped, pancake-shaped, and spherical geometries. These also naturally gives the criteria for the mean-field one- and two-dimensional regimes. Our predictions, including analytic forms for the density profiles, are shown to be in excellent agreement with numerical solutions. Importantly, the anisotropy of the interactions has a profound effect on the Thomas-Fermi and low-dimensional criteria.

DOI
10.1103/physreva.78.041601

Related papers

Mean-field regime of trapped dipolar Bose-Einstein condensates in one and two dimensions

Yongyong Cai, Matthias Rosenkranz, Zhen Lei +1 more

We derive rigorous one- and two-dimensional mean-field equations for cigar- and pancake-shaped dipolar Bose-Einstein condensates with arbitrary polarization angle. We show how the dipolar interaction modifies the contact interaction of the strongly confined atoms. In addition, our equations introduce a nonlocal potential, which is anisotropic for pancake-shaped condensates. We propose to observe this anisotropy via measurement of the condensate aspect ratio. We also derive analytically approximate density profiles from our equations. Both the numerical solutions of our reduced mean-field equations and the analytical density profiles agree well with numerical solutions of the full Gross-Pitaevskii equation while being more efficient to compute.

arXiv:1006.4950•Physical Review A•Oct 26, 2010•92 citations

Mean-field regime and Thomas–Fermi approximations of trapped Bose–Einstein condensates with higher-order interactions in one and two dimensions

Xinran Ruan, Yongyong Cai, Weizhu Bao

Abstract We derive rigorously one- and two-dimensional mean-field equations for cigar- and pancake-shaped Bose–Einstein condensates (BECs) with higher-order interactions (HOIs), which originate from shape-dependent confinement corrections to the effective two-body atomic interaction potential. We show how the higher-order interaction modifies the contact interaction of the strongly confined particles. Surprisingly, we find that the usual Gaussian profile assumption for the strongly confining direction is inappropriate for the cigar-shaped BEC case, and a Thomas–Fermi-type profile should be adopted instead. Based on the derived mean-field equations, the Thomas–Fermi densities are analyzed in the presence of the contact interaction and HOI, and considering the limit of large contact interaction and HOI. For both box and harmonic traps in one, two and three dimensions, we identify the analytical Thomas–Fermi densities, which depend on the competition between the contact interaction and the HOI.

arXiv:1511.00141•Journal of Physics B Atomic Molecular and Optical Physics•May 19, 2016•10 citations

Extension of the Thomas-Fermi approximation for trapped Bose-Einstein condensates with an arbitrary number of atoms

Antonio Muñoz Mateo, V. Delgado

By incorporating the zero-point energy contribution we derive simple and accurate extensions of the usual Thomas-Fermi (TF) expressions for the ground-state properties of trapped Bose-Einstein condensates that remain valid for an arbitrary number of atoms in the mean-field regime. Specifically, we obtain approximate analytical expressions for the ground-state properties of spherical, cigar-shaped, and disk-shaped condensates that reduce to the correct analytical formulas in both the TF and the perturbative regimes, and remain valid and accurate in between these two limiting cases. Mean-field quasi-one-dimensional (quasi-1D) and -2D condensates appear as simple particular cases of our formulation. The validity of our results is corroborated by an independent numerical computation based on the 3D Gross-Pitaevskii equation.

arXiv:cond-mat/0701695•Physical Review A•Dec 20, 2006•27 citations

Improved low-dimensional wave equations for cigar-shaped and disk-shaped dipolar Bose-Einstein condensates

Mitchell J. Knight, Thomas Bland, Parker, Nick G. +1 more

Within the formalism of the Gross-Pitaevskii equation, we derive effective one- and two-dimensional equations for cigar- and pancake-shaped dipolar Bose-Einstein condensates with arbitrary polarization angle. These are based on an ansatz for the condensate wavefunction whose width in the tightly-confined direction/s is treated variationally. The equations constitute a coupled partial differential for the low-dimensional wavefunction and algebraic equations for the width parameters. This approach accurately predicts the ground state densities of cigar-shaped and pancake-shaped dipolar Bose-Einstein condensates, and gives strong agreement with the three-dimensional results, even as the trapping is relaxed away from the strict quasi-one- and quasi-two-dimensional regimes. This approach offers a significant improvement over the standard one- and two-dimensional reduction.

arXiv:1908.02395•Aug 6, 2019•0 citations

Analysis beyond the Thomas-Fermi approximation of the density profiles of a miscible two-component Bose-Einstein condensate

Juan Polo, V. Ahufinger, Peter Mason +3 more

We investigate a harmonically trapped two-component Bose-Einstein condensate within the miscible regime, close to its boundaries, for different ratios of effective intra- and interspecies interactions. We derive analytically a universal equation for the density around the different boundaries in one, two, and three dimensions, for both the coexisting and spatially separated regimes. We also present a general procedure to solve the Thomas-Fermi approximation in all three spatial dimensionalities, reducing the complexity of the Thomas-Fermi problem for the spatially separated case in one and three dimensions to a single numerical inversion. Finally, we analytically determine the frontier between the two different regimes of the system.

arXiv:1502.05940•Physical Review A•May 27, 2015•28 citations

Exact Hydrodynamics of a Trapped Dipolar Bose-Einstein Condensate

Duncan H J O’Dell, S. Giovanazzi, Claudia Eberlein

We present exact results in the Thomas-Fermi regime for the statics and dynamics of a harmonically trapped Bose-Einstein condensate that has dipole-dipole interactions in addition to the usual s-wave contact interactions. Remarkably, despite the nonlocal and anisotropic nature of the dipolar interactions, the density profile in a general time-dependent harmonic trap is an inverted parabola. The evolution of the condensate radii is governed by local, ordinary differential equations, and as an example we calculate the monopole and quadrupole shape oscillation frequencies.

arXiv:cond-mat/0308096•Physical Review Letters•Jun 21, 2004•169 citations
We derive the criteria for the Thomas-Fermi regime of a dipolar Bose-Einstein condensate in cigar-shaped, pancake-shaped, and spherical geometries. These also naturally gives the criteria for the mean-field one- and two-dimensional regimes. Our predictions, including analytic forms for the density profiles, are shown to be in excellent agreement with numerical solutions. Importantly, the anisotropy of the interactions has a profound effect on the Thomas-Fermi and low-dimensional criteria.
We derive rigorous one- and two-dimensional mean-field equations for cigar- and pancake-shaped dipolar Bose-Einstein condensates with arbitrary polarization angle. We show how the dipolar interaction modifies the contact interaction of the strongly confined atoms. In addition, our equations introduce a nonlocal potential, which is anisotropic for pancake-shaped condensates. We propose to observe this anisotropy via measurement of the condensate aspect ratio. We also derive analytically approximate density profiles from our equations. Both the numerical solutions of our reduced mean-field equations and the analytical density profiles agree well with numerical solutions of the full Gross-Pitaevskii equation while being more efficient to compute.
Abstract We derive rigorously one- and two-dimensional mean-field equations for cigar- and pancake-shaped Bose–Einstein condensates (BECs) with higher-order interactions (HOIs), which originate from shape-dependent confinement corrections to the effective two-body atomic interaction potential. We show how the higher-order interaction modifies the contact interaction of the strongly confined particles. Surprisingly, we find that the usual Gaussian profile assumption for the strongly confining direction is inappropriate for the cigar-shaped BEC case, and a Thomas–Fermi-type profile should be adopted instead. Based on the derived mean-field equations, the Thomas–Fermi densities are analyzed in the presence of the contact interaction and HOI, and considering the limit of large contact interaction and HOI. For both box and harmonic traps in one, two and three dimensions, we identify the analytical Thomas–Fermi densities, which depend on the competition between the contact interaction and the HOI.
By incorporating the zero-point energy contribution we derive simple and accurate extensions of the usual Thomas-Fermi (TF) expressions for the ground-state properties of trapped Bose-Einstein condensates that remain valid for an arbitrary number of atoms in the mean-field regime. Specifically, we obtain approximate analytical expressions for the ground-state properties of spherical, cigar-shaped, and disk-shaped condensates that reduce to the correct analytical formulas in both the TF and the perturbative regimes, and remain valid and accurate in between these two limiting cases. Mean-field quasi-one-dimensional (quasi-1D) and -2D condensates appear as simple particular cases of our formulation. The validity of our results is corroborated by an independent numerical computation based on the 3D Gross-Pitaevskii equation.
Within the formalism of the Gross-Pitaevskii equation, we derive effective one- and two-dimensional equations for cigar- and pancake-shaped dipolar Bose-Einstein condensates with arbitrary polarization angle. These are based on an ansatz for the condensate wavefunction whose width in the tightly-confined direction/s is treated variationally. The equations constitute a coupled partial differential for the low-dimensional wavefunction and algebraic equations for the width parameters. This approach accurately predicts the ground state densities of cigar-shaped and pancake-shaped dipolar Bose-Einstein condensates, and gives strong agreement with the three-dimensional results, even as the trapping is relaxed away from the strict quasi-one- and quasi-two-dimensional regimes. This approach offers a significant improvement over the standard one- and two-dimensional reduction.
We investigate a harmonically trapped two-component Bose-Einstein condensate within the miscible regime, close to its boundaries, for different ratios of effective intra- and interspecies interactions. We derive analytically a universal equation for the density around the different boundaries in one, two, and three dimensions, for both the coexisting and spatially separated regimes. We also present a general procedure to solve the Thomas-Fermi approximation in all three spatial dimensionalities, reducing the complexity of the Thomas-Fermi problem for the spatially separated case in one and three dimensions to a single numerical inversion. Finally, we analytically determine the frontier between the two different regimes of the system.
We present exact results in the Thomas-Fermi regime for the statics and dynamics of a harmonically trapped Bose-Einstein condensate that has dipole-dipole interactions in addition to the usual s-wave contact interactions. Remarkably, despite the nonlocal and anisotropic nature of the dipolar interactions, the density profile in a general time-dependent harmonic trap is an inverted parabola. The evolution of the condensate radii is governed by local, ordinary differential equations, and as an example we calculate the monopole and quadrupole shape oscillation frequencies.