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In this paper, we propose a robust and efficient numerical method to compute the dynamics of the rotating two-component dipolar Bose-Einstein condensates (BEC). Using the rotating Lagrangian coordinates transform \cite{BMTZ2013}, we…

Computational Physics · Physics 2017-09-13 Qinglin Tang , Yong Zhang , Norbert Mauser

Modulational instability of a uniform two-dimensional binary Bose-Einstein condensate (BEC) in the presence of quantum fluctuations is studied. The analysis is based on the coupled Gross-Pitaevskii equations. It is shown that quantum…

Quantum Gases · Physics 2022-09-21 Sherzod R. Otajonov , Eduard N. Tsoy , Fatkhulla Kh. Abdullaev

We calculate the Bose-Einstein condensate (BEC) occupation statistics vs. the interparticle interaction in a dilute gas with a nonuniform condensate in a box trap within the Bogoliubov approach. The results are compared against the…

Quantum Gases · Physics 2021-03-01 Sergey V. Tarasov , Vladimir V. Kocharovsky , Vitaly V. Kocharovsky

We study the fluctuation of the number of particles in ideal Bose-Einstein condensates, both within the canonical and the microcanonical ensemble. Employing the Mellin-Barnes transformation, we derive simple expressions that link the…

Statistical Mechanics · Physics 2009-10-31 Martin Holthaus , Eva Kalinowski , Klaus Kirsten

In this paper we study the soliton dynamics of a high-density Bose-Einstein condensate (BEC) subject to a time-oscillating trap. The behavior of the BEC is described with a modified Gross-Pitaevskii equation (mGPE) which takes into account…

Quantum Gases · Physics 2021-02-24 R. Flores-Calderón , J. Fujioka , A. Espinosa-Cerón

Based on the canonical ensemble, we suggested the simple scheme for taking into account Gaussian fluctuations in a finite system of ideal boson gas. Within framework of scheme we investigated the influence of fluctuations on the particle…

Statistical Mechanics · Physics 2015-06-04 A Petrova , O Nedopekin , D Tayurskii , Q A Wang

Transition temperatures $T_{c}$ calculated using the BCS model electron-phonon interaction without any adjustable parameters agree with empirical values for quasi-2D cuprate superconductors. They follow from a two-dimensional gas of…

Superconductivity · Physics 2009-11-07 M. Casas , M. de Llano , A. Puente , A. Rigo , M. A. Solis

Bose-Einstein condensates are suitable systems for studying fundamental aspects of quantum backreaction. Here the backreaction problem in 1D condensates is considered from the perspective of energy and momentum conservation. By assuming the…

Quantum Physics · Physics 2024-08-29 Caio C. Holanda Ribeiro

This work is concerned with the construction and analysis of structure-preserving Galerkin methods for computing the dynamics of rotating Bose-Einstein condensate (BEC) based on the Gross-Pitaevskii equation with angular momentum rotation.…

Numerical Analysis · Mathematics 2024-05-28 Meng Li , Junjun Wang , Zhen Guan , Zhijie Du

The quantum and thermal fluctuations of the phase are investigated in a cold Bose gas confined by a double well trap. The coherence of the system is discussed in terms of the visibility of interference fringes in both momentum and…

Condensed Matter · Physics 2009-11-07 L. Pitaevskii , S. Stringari

We determine the effects of quantum fluctuations about the T=0 mean field solution of the BCS-BEC crossover in a dilute Fermi gas using the functional integral method. These fluctuations are described in terms of the zero point motion of…

Other Condensed Matter · Physics 2008-03-20 Roberto B. Diener , Rajdeep Sensarma , Mohit Randeria

Using the linearized version of the time dependent Gross-Pitaevskii equation we calculate the dynamic response of a Bose-Einstein condensed gas to periodic density and particle perturbations. The zero temperature limit of the…

Quantum Gases · Physics 2019-02-20 Sandro Stringari

In this paper, we propose an efficient and accurate numerical method for computing the dynamics of rotating two-component Bose--Einstein condensates (BECs) which is described by coupled Gross--Pitaevskii equations (CGPEs) with an angular…

Numerical Analysis · Mathematics 2013-06-10 Ming Ju , Qinglin Tang , Yanzhi Zhang

We investigate the fluctuation effect of the di-fermion field in the crossover from Bardeen-Cooper-Schrieffer (BCS) pairing to a Bose-Einstein condensate (BEC) in a relativistic superfluid. We work within the boson-fermion model obeying a…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jian Deng , Jin-cheng Wang , Qun Wang

The quantum fluctuation effects in the time-of-flight (TOF) experiment for a condensate released from an optical lattice potential is studied within the truncated Wigner approximation. By investigating both the spatial and momentum density…

Quantum Gases · Physics 2010-09-29 Shiang Fang , Ray-Kuang Lee , Daw-Wei Wang

In a joint experimental and theoretical effort, we report on the formation of a macro-droplet state in an ultracold bosonic gas of erbium atoms with strong dipolar interactions. By precise tuning of the s-wave scattering length below the…

Quantum Gases · Physics 2016-11-30 L. Chomaz , S. Baier , D. Petter , M. J. Mark , F. Wächtler , L. Santos , F. Ferlaino

Using the Gaussian pair fluctuation theory, we investigate quantum fluctuations of a strongly interacting two-dimensional chiral \textit{p}-wave Fermi superfluid at the transition from a Bose-Einstein condensate (BEC) to a topologically…

Quantum Gases · Physics 2018-12-12 Hui Hu , Brendan C. Mulkerin , Lianyi He , Jia Wang , Xia-Ji Liu

We consider the dephasing of two internal states |0> and |1> of a trapped impurity atom, a so-called atomic quantum dot (AQD), where only state |1> couples to a Bose-Einstein condensate (BEC). A direct relation between the dephasing of the…

Quantum Physics · Physics 2007-05-23 M. Bruderer , D. Jaksch

We study the dynamics of a single and a pair of vortices in quasi two-dimensional Bose-Einstein condensates at finite temperatures. We use the stochastic Gross-Pitaevskii equation, which is the Langevin equation for the Bose-Einstein…

Quantum Gases · Physics 2014-02-04 S. Gautam , Arko Roy , Subroto Mukerjee

We consider a trapped Bose--Einstein condensate (BEC) with a highly quantized vortex. For the BEC with a doubly, triply or quadruply quantized vortex, the numerical calculations have shown that the Bogoliubov--de Gennes equations, which…

Other Condensed Matter · Physics 2009-11-11 Eriko Fukuyama , Makoto MIne , Masahiko Okumura , Tomoka Sunaga , Yoshiya Yamanaka