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Related papers: Basic theory tools for degenerate Fermi gases

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We consider a two-component Fermi gas with a contact interaction from the BCS regime to the unitary limit. Starting from the idea that many-body effects should not depend on short-distance or high-momentum physics which is encoded in the…

Quantum Gases · Physics 2021-06-15 M. Urban , S. Ramanan

We present a description of the behavior of a superfluid gas of fermions in the presence of a Feshbach resonance over the complete range of magnetic field detunings. Starting from a resonance Hamiltonian, we exploit a functional method to…

Soft Condensed Matter · Physics 2009-02-05 J. N. Milstein , S. J. J. M. F. Kokkelmans , M. J. Holland

We consider a dilute gas of neutral unpolarized fermionic atoms at zero temperature.The atoms interact via a short range (tunable) attractive interaction. We demonstrate analytically a curious property of the gas at unitarity. Namely, the…

Other Condensed Matter · Physics 2009-11-13 Michael Seidl , Rajat K. Bhaduri

Quantum-degenerate Fermi gases provide a remarkable opportunity to study strongly interacting fermions. In contrast to other Fermi systems, such as superconductors, neutron stars or the quark-gluon plasma, these gases have low densities and…

Superconductivity · Physics 2007-05-23 M. W. Zwierlein , J. R. Abo-Shaeer , A. Schirotzek , C. H. Schunck , W. Ketterle

I give a unified perspective on the properties of a variety of quantum liquids using the theory of quantum phase transitions. A central role is played by a zero density quantum critical point which is argued to control the properties of the…

Quantum Gases · Physics 2015-05-28 Subir Sachdev

We study many-body contributions to the effective interaction between fermions in a three-component Fermi mixture. We find that effective interactions induced by the third component can lead to a phase diagram different from that predicted…

Quantum Gases · Physics 2015-05-14 J. -P. Martikainen , J. J. Kinnunen , P. Torma , C. J. Pethick

This thesis presents experiments probing physics in the crossover between Bose-Einstein condensation (BEC) and BCS superconductivity using an ultracold gas of atomic fermions. Scattering resonances in these ultracold gases (known as…

Other Condensed Matter · Physics 2007-05-23 C. Regal , D. S. Jin

We study static superfluid properties of alkali-earth-like Fermi atomic systems in the presence of orbital Feshbach resonance. Using a two-band description of the ground state and excited state and a mean-field approximation of the…

Quantum Gases · Physics 2024-09-25 Andrew Vincent , Theja N. De Silva

We have studied interacting and non-interacting quantum degenerate Fermi gases in a three-dimensional optical lattice. We directly image the Fermi surface of the atoms in the lattice by turning off the optical lattice adiabatically. Due to…

Superconductivity · Physics 2009-11-10 Michael Köhl , Henning Moritz , Thilo Stöferle , Kenneth Günter , Tilman Esslinger

We present a rigorous derivation of the BCS gap equation for superfluid fermionic gases with point interactions. Our starting point is the BCS energy functional, whose minimizer we investigate in the limit when the range of the interaction…

Mathematical Physics · Physics 2014-03-12 Gerhard Bräunlich , Christian Hainzl , Robert Seiringer

In this Rapid Communication, we investigate the universal properties of a spin-polarized two-component Fermi gas in one dimension (1D) using Bethe ansatz. We discuss the quantum phases and phase transitions by obtaining exact results for…

Quantum Gases · Physics 2016-10-12 Wen-Bin He , Yang-Yang Chen , Shizhong Zhang , Xi-Wen Guan

We apply the S-matrix based finite temperature formalism to non-relativistic Bose and Fermi gases in 1+1 and 2+1 dimensions. In the 2+1 dimensional case, the free energy is given in terms of Roger's dilogarithm in a way analagous to the…

Mathematical Physics · Physics 2008-11-26 André LeClair

We suggest that the exchange fluctuations close to a Feshbach resonance in a two-component Fermi gas can result in an effective p-wave attractive interaction. On the BCS side of a Feshbach resonance, the magnitude of this effective…

Other Condensed Matter · Physics 2007-06-07 Sergio Gaudio , Jason Jackiewicz , Kevin S. Bedell

We study a trapped two-dimensional spin-imbalanced Fermi gas over a range of temperatures. In the moderate temperature regime, associated with current experiments, we find reasonable semi-quantitative agreement with the measured density…

Quantum Gases · Physics 2016-09-09 Chien-Te Wu , Brandon M. Anderson , Rufus Boyack , K. Levin

We theoretically examine a zero-temperature system of Fermi degenerate atoms coupled to bosonic molecules via collisionless rapid adiabatic passage across a Feshbach resonance, focusing on saturation of the molecular conversion efficiency…

Atomic Physics · Physics 2016-09-08 Matt Mackie , Olavi Dannenberg

We numerically study the transport properties of a two-dimensional Fermi gas in a weakly and strongly interacting regimes, in the range of temperatures close to the transition to a superfluid phase. For that we excite sound waves in a…

Quantum Gases · Physics 2024-05-15 Krzysztof Gawryluk , Mirosław Brewczyk

Magnetically tunable Feshbach resonances were employed to associate cold diatomic molecules in a series of experiments involving both atomic Bose as well as two spin component Fermi gases. This review illustrates theoretical concepts of…

Other Condensed Matter · Physics 2007-05-23 Thorsten Koehler , Krzysztof Goral , Paul S. Julienne

We study pairing of an interacting three component Fermi gas in two dimensions. By using a mean field theory to decouple the interactions between different pairs of Fermi components, we study the free energy landscapes as a function of…

Other Condensed Matter · Physics 2021-09-08 Theja N. De Silva

Unitary Fermi gases, where the scattering length is large compared to the interparticle spacing, can have universal properties, which are independent of the details of the interparticle interactions when the range of the scattering…

Other Condensed Matter · Physics 2011-07-19 J. E. Thomas , J. Kinast , A. Turlapov

Trapped ultracold Fermi gases provide a system that can be tuned between the BCS and BEC regimes by means of a magnetic-field Feshbach resonance. Condensation of fermionic atom pairs in a $^{40}$K gas was demonstrated experimentally by a…

Strongly Correlated Electrons · Physics 2011-09-13 Qijin Chen , C. A. Regal , M. Greiner , D. S. Jin , K. Levin