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Related papers: The BCS gap equation for spin-polarized fermions

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We present a numerical study of the one-dimensional BCS-BEC crossover of a spin-imbalanced Fermi gas. The crossover is described by the Bose-Fermi resonance model in a real space representation. Our main interest is in the behavior of the…

Quantum Gases · Physics 2013-05-29 F. Heidrich-Meisner , A. E. Feiguin , U. Schollwoeck , W. Zwerger

We investigate the finite temperature properties of an ultracold atomic Fermi gas with spin population imbalance in a highly elongated harmonic trap. Previous studies at zero temperature showed that the gas stays in an exotic spatially…

Statistical Mechanics · Physics 2008-08-07 Xia-Ji Liu , Hui Hu , Peter D. Drummond

We investigate pairing in a strongly interacting two-component Fermi gas with positive scattering length. In this regime, pairing occurs at temperatures above the superfluid critical temperature; unbound fermions and pairs coexist in…

We revisit early suggestions to observe spin-charge separation (SCS) in cold-atom settings {in the time domain} by studying one-dimensional repulsive Fermi gases in a harmonic potential, where pulse perturbations are initially created at…

Statistical Mechanics · Physics 2022-09-21 Stefano Scopa , Pasquale Calabrese , Lorenzo Piroli

We consider a spin imbalanced Fermi gas at zero temperature in the normal phase on the BCS side of the BCS-BEC crossover and around unitarity. We compute the critical polarization for pairing, the correlated occupation numbers and the…

Quantum Gases · Physics 2020-01-10 David Durel , Michael Urban

The polarization produced by the relative displacement of the potentials trapping two spin species of a dilute Fermi gas with $N_\ua=N_\da$ is calculated at unitarity by assuming phase separation between the superfluid and a spin polarized…

Soft Condensed Matter · Physics 2011-10-18 A. Recati , I. Carusotto , C. Lobo , S. Stringari

We discuss the superfluid phase transition of a strongly interacting Fermi gas with unequal (asymmetric) chemical potentials in two pairing hyperfine states, and map out its phase diagram near the BCS-BEC crossover. Our approach includes…

Statistical Mechanics · Physics 2007-05-23 Xia-Ji Liu , Hui Hu

A two-dimensional (2D) assembly of noninteracting, temperature-dependent, composite-boson Cooper pairs (CPs) in chemical and thermal equilibrium with unpaired fermions is examined in a binary boson-fermion statistical model as the…

Superconductivity · Physics 2016-08-16 M. Casas , N. J. Davidson , M. de Llano , T. A. Mamedov , A. Puente , R. M. Quick , A. Rigo , M. A. Solís

The non-relativistic $G_0 G$ formalism of BCS-BEC crossover at finite temperature is extended to relativistic fermion systems. The uncondensed pairs contribute a pseudogap to the fermion excitations. The theory recovers the BCS mean field…

High Energy Physics - Phenomenology · Physics 2008-11-26 Lianyi He , Pengfei Zhuang

We consider non-zero temperature properties of the polarized two-component Fermi gas. We point out that stable polarized paired states which are more stable than their phase separated counterparts with unpolarized superfluid region can…

Statistical Mechanics · Physics 2009-11-11 Jani-Petri Martikainen

We in this paper investigate the phase diagram associated with the BCS-BEC crossover of a three-component ultracold superfluid-Fermi-gas of different chemical-potentials and equal masses in two dimensions. The gap order parameter and number…

Quantum Gases · Physics 2015-06-04 Jiajia Du , Junjun Liang , J. -Q. Liang

A two-dimensional (2D) assembly of noninteracting, temperature-dependent, composite-boson Cooper pairs (CPs) in chemical and thermal equilibrium with unpaired fermions is examined in a binary boson-fermion statistical model as the…

Superconductivity · Physics 2016-08-15 M. Casas , N. J. Davidson , M. de Llano , T. A. Mamedov , A. Puente , R. M. Quick , A. Rigo , M. A. Solís

We investigate the phase separation of resonantly interacting fermions in a trap with imbalanced spin populations, both at zero and at finite temperatures. We directly minimize the thermodynamical potential under the local density…

Other Condensed Matter · Physics 2009-02-05 W. Yi , L. -M. Duan

We determine the energetically lowest lying states in the BEC-BCS crossover regime of s-wave interacting two-component Fermi gases under harmonic confinement by solving the many-body Schrodinger equation using two distinct approaches.…

Other Condensed Matter · Physics 2009-11-13 J. von Stecher , C. H. Greene , D. Blume

We address the phase of a highly polarized Fermi gas across a narrow Feshbach resonance starting from the problem of a single down spin fermion immersed in a Fermi sea of up spins. Both polaron and pairing states are considered using the…

Quantum Gases · Physics 2015-03-19 Ran Qi , Hui Zhai

We study the phase diagram of mass- and spin-imbalanced unitary Fermi gases, in search for the emergence of spatially inhomogeneous phases. To account for fluctuation effects beyond the mean-field approximation, we employ renormalization…

Quantum Gases · Physics 2015-06-11 Dietrich Roscher , Jens Braun , Joaquín E. Drut

Fermion systems with more than two components can exhibit pairing condensates of much more complex structure than the well-known single BCS condensate of spin-up and spin-down fermions. In the framework of the exactly solvable SO(8)…

Mathematical Physics · Physics 2015-05-14 G. F. Bertsch , J. Dukelsky , B. Errea , C. Esebbag

We prove that the critical temperature for the BCS gap equation is given by $T_c = \mu (8/\pi e^{\gamma -2} + o(1)) e^{\pi/(2\sqrt \mu a)}$ in the low density limit $\mu\to 0$. The formula holds for a suitable class of interaction…

Mathematical Physics · Physics 2009-11-13 Christian Hainzl , Robert Seiringer

Using many-body results available from diagrammatic and {\it ab initio} Monte Carlo calculations we analyze the phase diagram $\mu=(\mu_{\uparrow}+\mu_{\downarrow})/2$ versus $h=(\mu_{\uparrow}-\mu_{\downarrow})/2$ of a unitary Fermi gas at…

Other Condensed Matter · Physics 2009-05-13 I. Bausmerth , A. Recati , S. Stringari

We study the BCS energy gap $\Xi$ in the high-density limit and derive an asymptotic formula, which strongly depends on the strength of the interaction potential $V$ on the Fermi surface. In combination with the recent result by one of us…

Mathematical Physics · Physics 2023-12-21 Joscha Henheik , Asbjørn Bækgaard Lauritsen