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Related papers: Pairing transitions in a Binary Bose Gas

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The condensation of fermion pairs lies at the heart of superfluidity. However, for strongly correlated systems with reduced dimensionality the mechanisms of pairing and condensation are still not fully understood. In our experiment we use…

Quantum Gases · Physics 2015-06-11 M. G. Ries , A. N. Wenz , G. Zürn , L. Bayha , I. Boettcher , D. Kedar , P. A. Murthy , M. Neidig , T. Lompe , S. Jochim

The phases of a Bose-Einstein condensate (BEC) with light-induced spin-orbit coupling (SOC) are studied within the mean-field approximation. The mixed BEC phase, in which the system condenses in a superposition of two plane wave states, is…

Quantum Gases · Physics 2015-06-16 Qin-Qin Lü , Daniel E. Sheehy

For the Cooper/BCS model interaction in superconductors (SCs) it is shown: a) how BCS-Bose crossover picture transition temperatures Tc, defined self-consistently by both the gap and fermion-number equations, require unphysically large…

Superconductivity · Physics 2007-05-23 M. de Llano , F. J. Sevilla , M. A. Solis , J. J. Valencia

We investigate the uniform spin susceptibility $\chi_{\rm s}$ in the BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein condensation) crossover regime of an ultracold Fermi gas. Including pairing fluctuations within the framework of an…

Quantum Gases · Physics 2015-10-16 H. Tajima , T. Kashimura , R. Hanai , R. Watanabe , Y. Ohashi

We study the dynamics of two-component atomic Bose gases initially in a mixture encountering a sudden quench of the inter-species interactions. The dynamics above the critical temperature $T_c$ is studied using a leading order large-N…

Quantum Gases · Physics 2013-04-11 Chih-Chun Chien , Fred Cooper

The BCS-to-BEC crossover, as well as the nature of Cooper pairs, in a superconducting and Fermi superfluid medium is studied from the exact ground state wavefunction of the reduced BCS Hamiltonian. As the strength of the interaction…

Superconductivity · Physics 2009-11-11 Gerardo Ortiz , Jorge Dukelsky

In this paper, we study Bose-Einstein condensation of Rydberg-dressed atoms considering finite range interactions. We use Hartree-Fock-Bogoliubov approximation based on Mean-Field approach. Moreover, within this approximation modified by…

Quantum Gases · Physics 2022-10-03 Asliddin Khudoyberdiev , Zabardast Narzikulov , B. Tanatar

Phase transitions are ubiquitous in our three-dimensional world. By contrast most conventional transitions do not occur in infinite uniform two-dimensional systems because of the increased role of thermal fluctuations. Here we explore the…

We investigate the BCS-BEC crossover taking into account an additional three-body interaction, which is essentially the scattering between the Cooper pairs and the newly formed bosons. We show that if the two-body interaction is attractive,…

Quantum Gases · Physics 2011-10-18 Raka Dasgupta

We study the BCS-Bose Einstein Condensation (BEC) crossover of a three dimensional spin polarized Fermi gas with Rashba spin-orbital-coupling (SOC). At finite temperature, the effects of non-condensed pairs due to the thermal excitation are…

Quantum Gases · Physics 2016-06-24 Chang-Yan Wang , Yan He

At low-temperatures a gas of bosons will undergo a phase transition into a quantum state of matter known as a Bose-Einstein condensate (BEC), in which a large fraction of the particles will occupy the ground state simultaneously. Here we…

Bardeen-Cooper-Schrieffer (BCS) theory describes a superconducting transition as a single critical point where the gap function or, equivalently, the order parameter vanishes uniformly in the entire system. We demonstrate that in…

Superconductivity · Physics 2020-04-22 Albert Samoilenka , Egor Babaev

We investigate the crossover from Bardeen-Cooper-Schrieffer (BCS) superfluidity to Bose-Einstein condensation (BEC) in a two-dimensional Fermi gas at T=0 using the fixed-node diffusion Monte Carlo method. We calculate the equation of state…

Quantum Gases · Physics 2015-03-17 G. Bertaina , S. Giorgini

The equilibrium properties of a weakly interacting atomic Bose gas across the Berezinskii-Kosterlitz-Thouless (BKT) and Bose-Einstein condensation (BEC) phase transitions are numerically investigated through a dimensionality crossover from…

Quantum Gases · Physics 2024-12-13 Nick Keepfer , I-Kang Liu , Franco Dalfovo , Nick Proukakis

The present contribution explores phase transitions that occur in the ground state (GS) of spin-1 Bose-Einstein condensates (BECs) with spin-orbit coupling (SOC) under the action of gradient magnetic fields. By solving the corresponding…

Quantum Gases · Physics 2025-10-21 Xin-Feng Zhang , Huan-Bo Luo , Josep Batle , Bin Liu , Yongyao Li

We investigate pairing fluctuation effects in a two band fermionic system, where a shallow band in the Bardeen--Cooper--Schrieffer--Bose--Einstein condensation (BCS-BEC) crossover regime is coupled with a weakly interacting deep band.…

Superconductivity · Physics 2020-01-23 Hiroyuki Tajima , Andrea Perali , Pierbiagio Pieri

We investigate a mix-dimensional Fermi-Fermi mixture in which one species is confined in two-dimensional(2D) space while the other is free in three-dimensional space(3D). We determine the superfluid transition temperature $T_{c}$ for the…

Superconductivity · Physics 2015-05-27 Xiaosen Yang , Beibing Huang , Shaolong Wan

Bose-Einstein condensation happens as a gas of bosons is cooled below its transition temperature, and the ground state becomes macroscopically occupied. The phase transition occurs in the thermodynamic limit of many particles. However,…

Quantum Gases · Physics 2023-03-24 Fredrik Brange , Tuomas Pyhäranta , Eppu Heinonen , Kay Brandner , Christian Flindt

We investigate thermally excited, dipolar Bose-Einstein condensates. Quasi-particle excitations of the atomic cloud cause density fluctuations which can induce the collapse of the condensate if the inter-particle interaction is attractive.…

Quantum Gases · Physics 2013-10-15 Andrej Junginger , Manuel Kreibich , Jörg Main , Günter Wunner

Three distinct types of behaviour have recently been identified in the two-dimensional trapped bosonic gas, namely; a phase coherent Bose-Einstein condensate (BEC), a Berezinskii-Kosterlitz-Thouless-type (BKT) superfluid and normal gas…

Statistical Mechanics · Physics 2007-05-23 Daniel Schumayer , David A. W. Hutchinson