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

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The Fermi polaron problem, which describes a mobile impurity that interacts with a spin-polarized Fermi sea, is a paradigmatic system in quantum many-body physics and has been challenging to address quantitatively in its strong coupling…

Quantum Gases · Physics 2025-11-26 S. Ramachandran , S. Jensen , Y. Alhassid

We study the phase separation of a spin polarized Fermi gas with spin-orbit coupling near a wide Feshbach resonance. As a result of the competition between spin-orbit coupling and population imbalance, the phase diagram for a uniform gas…

Quantum Gases · Physics 2011-10-03 W. Yi , G. -C. Guo

We study an ultracold trapped Fermi gas of atoms in two hyperfine states with unequal populations. In this situation the usual BCS pairing is suppressed and non-standard pairing mechanisms become important. These are treated by solving the…

Other Condensed Matter · Physics 2009-11-11 Paolo Castorina , Marcella Grasso , Micaela Oertel , Michael Urban , Dario Zappala

We investigate the dynamical properties of a superfluid gas of trapped fermionic atoms in the BCS phase. As a simple example we consider the reaction of the gas to a slow rotation of the trap. It is shown that the currents generated by the…

Other Condensed Matter · Physics 2009-11-10 Michael Urban

We investigate the crossover from BCS pairing to molecular BEC in an atomic gas with two fermion species with masses $m_\up \ne m_\dn$ tuned through a Feshbach resonance. We present results for the T=0 equation of state as a function of the…

Quantum Gases · Physics 2015-05-13 Roberto B. Diener , Mohit Randeria

We study a gas of fermions undergoing a wide resonance s-wave BCS-BEC crossover, in the BEC regime at zero temperature. We calculate the chemical potential and the speed of sound of this Bose-condensed gas, as well as the condensate…

Superconductivity · Physics 2009-11-11 J. Levinsen , V. Gurarie

Departures of thermodynamic properties of three-dimensional superfluid $^3$He from the predictions of BCS theory are analyzed. Attention is focused on deviations of the ratios $\Delta(T=0)/T_c$ and $[C_s(T_c)-C_n(T_c)]/C_n(T_c)$ from their…

Superconductivity · Physics 2009-11-11 M. V. Zverev , V. A. Khodel , J. W. Clark

The two-component Fermi gas is the simplest fermion system displaying superfluidity, and as such finds applications ranging from the theory of superconductivity to QCD. Ultracold atomic gases provide an exceptionally clean realization of…

Other Condensed Matter · Physics 2015-06-25 M. M. Parish , F. M. Marchetti , A. Lamacraft , B. D. Simons

The pairing of fermions is at the heart of superconductivity and superfluidity. The recent experimental realization of strongly interacting atomic Fermi gases has opened a new, controllable way to study novel forms of pairing and…

Soft Condensed Matter · Physics 2009-11-13 Yong-il Shin , Christian H. Schunck , Andre Schirotzek , Wolfgang Ketterle

We have performed a fully non-perturbative calculation of the thermal properties of a system of spin 1/2 fermions in 3D in the unitary regime. We have determined the critical temperature for the superfluid-normal phase transition. The…

Statistical Mechanics · Physics 2009-11-11 Aurel Bulgac , Joaquin E. Drut , Piotr Magierski

In the two-component Fermi gas with a contact interaction, a pseudogap regime can exist at temperatures between the superfluid critical temperature $T_c$ and a temperature $T^* > T_c$. This regime is characterized by pairing correlations…

Quantum Gases · Physics 2020-03-11 S. Jensen , C. N. Gilbreth , Y. Alhassid

We determine the size of the critical region of the superfluid transition in the BCS-BEC crossover of a three-dimensional fermion gas, using a renormalization-group approach to a bosonic theory of pairing fluctuations. For the unitary Fermi…

Quantum Gases · Physics 2016-03-08 T. Debelhoir , N. Dupuis

We investigate strong-coupling corrections to single-particle excitations in the normal state of a spin-polarized unitary Fermi gas. Within the framework of an extended T-matrix approximation, we calculate the single-particle density of…

Quantum Gases · Physics 2015-06-17 Takashi Kashimura , Ryota Watanabe , Yoji Ohashi

We analyze the zero temperature phase diagram for an asymmetric two-component Fermi gas as a function of mass anisotropy and population imbalance. We identify regions corresponding to normal, or uniform/non-uniform superfluid phases, and…

Superconductivity · Physics 2007-05-23 M. Iskin , C. A. R. Sa de Melo

We consider a gas of fermions with non-zero spin at temperature $T$ and chemical potential $\mu$. We show that if the range of the interparticle interaction is small compared to the mean particle distance, the thermodynamic pressure differs…

Mathematical Physics · Physics 2015-06-26 Robert Seiringer

We study the zero-temperature phase diagram of the 2D spin-imbalanced Fermi gas with short-ranged attractive interactions using the recently developed neural network variational Monte Carlo method with the AGPs FermiNet Ansatz. The…

We study pseudogap behaviors of ultracold Fermi gases in the BCS-BEC crossover region. We calculate the density of states (DOS), as well as the single-particle spectral weight, above the superfluid transition temperature $T_{\rm c}$…

Quantum Gases · Physics 2015-05-13 S. Tsuchiya , R. Watanabe , Y. Ohashi

We study the zero temperature properties of a trapped polarized Fermi gas at unitarity by assuming phase separation between an unpolarized superfluid and a polarized normal phase. The effects of the interaction are accounted using the…

Other Condensed Matter · Physics 2009-11-13 A. Recati , C. Lobo , S. Stringari

We investigate strong-coupling effects on normal state properties of an ultracold Fermi gas. Within the framework of $T$-matrix approximation in terms of pairing fluctuations, we calculate the single-particle density of states (DOS), as…

Quantum Gases · Physics 2013-05-29 Shunji Tsuchiya , Ryota Watanabe , Yoji Ohashi

We study translation-invariant quasi-free states for a system of fermions with two-particle interactions. The associated energy functional is similar to the BCS functional but includes also direct and exchange energies. We show that for…

Mathematical Physics · Physics 2015-06-16 Gerhard Bräunlich , Christian Hainzl , Robert Seiringer