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Related papers: Pair Correlations in the Two-Dimensional Fermi Gas

200 papers

Ultracold atomic gases with short-range interactions are characterized by a number of universal species-independent relations. Many of these relations involve the two-body Tan contact. Employing the canonical ensemble, we determine the Tan…

Quantum Gases · Physics 2015-06-16 Yangqian Yan , D. Blume

We investigate strong-coupling properties of a two-dimensional ultracold Fermi gas in the normal phase. In the three-dimensional case, it has been shown that the so-called pseudogap phenomena can be well described by a (non-self-consistent)…

Quantum Gases · Physics 2016-10-31 Morio Matsumoto , Ryo Hanai , Daisuke Inotani , Yoji Ohashi

We consider pairing in a dilute system of Fermions with a short-range interaction. While the theory is ill-defined for a contact interaction, the BCS equations can be solved in the leading order of low-energy effective field theory. The…

Nuclear Theory · Physics 2011-07-18 Thomas Papenbrock , George F. Bertsch

We present a theoretical interpretation of radio-frequency (RF) pairing gap experiments in trapped atomic Fermi gases, over the entire range of the BCS-BEC crossover, for temperatures above and below $T_c$. Our calculated RF excitation…

Soft Condensed Matter · Physics 2011-09-13 Yan He , Qijin Chen , K. Levin

Thermodynamic properties of matter are conveniently expressed as functional relations between variables known as equations of state. Here we experimentally determine the compressibility, density and pressure equations of state for an…

Quantum Gases · Physics 2016-02-12 K. Fenech , P. Dyke , T. Peppler , M. G. Lingham , S. Hoinka , H. Hu , C. J. Vale

We have studied the transition from two to three dimensions in a low temperature weakly interacting $^6$Li Fermi gas. Below a critical atom number, $N_{2D}$, only the lowest transverse vibrational state of a highly anisotropic oblate…

Quantum Gases · Physics 2011-03-16 P. Dyke , E. D. Kuhnle , S. Whitlock , H. Hu , M. Mark , S. Hoinka , M. Lingham , P. Hannaford , C. J. Vale

We consider trapped atomic Fermi gases with Feshbach-resonance enhanced interactions in pseudogap and superfluid temperatures. We calculate the spectrum of RF(or laser)-excitations for transitions that transfer atoms out of the superfluid…

Superconductivity · Physics 2016-08-31 J. Kinnunen , M. Rodriguez , P. Torma

We measure radiofrequency (rf) spectra of the homogeneous unitary Fermi gas at temperatures ranging from the Boltzmann regime through quantum degeneracy and across the superfluid transition. For all temperatures, a single spectral peak is…

Pairing between fermions that attract each other, reveal itself to the macroscopic world in the form of superfluidity. Since the discovery of fermionic superfluidity, intense search has been going on to find various unconventional forms of…

Quantum Gases · Physics 2009-06-12 O. Dutta , M. Lewenstein

Ultracold Fermi gases subject to tight transverse confinement offer a highly controllable setting to study the two-dimensional (2D) BCS to Berezinskii-Kosterlitz-Thouless superfluid crossover. Achieving the 2D regime requires confining…

Quantum Gases · Physics 2016-01-20 P. Dyke , K. Fenech , T. Peppler , M. G. Lingham , S. Hoinka , W. Zhang , B. Mulkerin , H. Hu , X. -J. Liu , C. J. Vale

The possibilities of pairing in two-dimensional boson-fermion mixtures are carefully analyzed. It is shown that the boson-induced attraction between two identical fermions dominates the p-wave pairing at low density. For a given fermion…

Superconductivity · Physics 2009-11-10 J. Mur-Petit , A. Polls , M. Baldo , H. -J. Schulze

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

Quantum states of a two-component Fermi trapped gas are described by introducing an effective trap frequency, determined via variational techniques. Closed expressions for the contribution of a contact interaction potential to the total…

Other Condensed Matter · Physics 2009-11-10 R. Jáuregui , R. Paredes , G. Toledo Sánchez

We use a BCS-type variational wavefunction to study attractively-interacting quasi one-dimensional (1D) fermionic atomic gases, motivated by cold-atom experiments that access the 1D regime using an anisotropic harmonic trapping potential…

Quantum Gases · Physics 2015-07-16 Stephen Kudla , Dominique M. Gautreau , Daniel E. Sheehy

We investigate pseudogap phenomena originating from pairing fluctuations in the BCS-BEC crossover regime of a two-dimensional Fermi gas in a harmonic trap. Including pairing fluctuations within a $T$-matrix theory and effects of a trap…

Quantum Gases · Physics 2015-06-05 Ryota Watanabe , Shunji Tsuchiya , Yoji Ohashi

The nature of pseudogap lies at the heart of strongly-interacting superconductivity and superfluidity. With known pairing interactions, unitary Fermi gases provide an ideal testbed to verify whether a pseudogap can arise from many-body…

The existence of a pseudogap in unitary Fermi gases has recently been established and measured experimentally [Li et al., Nature 626, 288 (2024)]. This lends strong support for the pairing origin as the mechanism of the pseudogap in Fermi…

Quantum Gases · Physics 2026-04-08 Chuping Li , Lin Sun , Kaichao Zhang , Junru Wu , Yuxuan Wu , Dingli Yuan , Pengyi Chen , Qijin Chen

We relate short-range correlations in ultracold atomic Fermi gases to the entropy of the system over the entire temperature, $T$, vs. coupling strength, $-1/k_Fa$, plane. In the low temperature limit the entropy is dominated by phonon…

Quantum Gases · Physics 2009-08-31 Zhenhua Yu , Georg M. Bruun , Gordon Baym

An effective interaction between fermions in a Bose-Fermi mixture is derived. It is induced by density fluctuations of the bosonic background. The contributions from states containing both one and two virtual phonons are taken into account…

Soft Condensed Matter · Physics 2008-12-18 F. Matera

We derive analytical expressions for the frequency and damping of the lowest collective modes of a two-dimensional Fermi gas using kinetic theory. For strong coupling, we furthermore show that pairing correlations overcompensate the effects…

Quantum Gases · Physics 2013-05-30 Stefan K. Baur , Enrico Vogt , Michael Köhl , Georg M. Bruun