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Related papers: Universal Quantum Viscosity in a Unitary Fermi Gas

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Elaborated calculations of the shear and the bulk viscosities in the hadron gas, using the ultrarelativistic quantum molecular dynamics (UrQMD) model cross sections, are made. These cross sections are analyzed and improved. A special…

High Energy Physics - Phenomenology · Physics 2013-09-23 Oleg Moroz

We calculate the damping of the Bogoliubov-Anderson mode in a one-dimensional two-component attractive Fermi gas for arbitrary coupling strength within a quantum hydrodynamic approach. Using the Bethe-Ansatz solution of the 1D BCS-BEC…

Statistical Mechanics · Physics 2009-11-11 M. Punk , W. Zwerger

We precisely test scale invariance and local thermal equilibrium in the hydrodynamic expansion of a Fermi gas of atoms as a function of interaction strength. After release from an anisotropic optical trap, we observe that a resonantly…

Quantum Gases · Physics 2014-02-19 E. Elliott , J. A. Joseph , J. E. Thomas

The shear viscosity tensor of the superfluid Fermi gas in p-wave state with weak interaction is calculated at low temperatures, by using the Boltzmann equation approach. We consider the transition probabilities for the binary, decay and…

Quantum Gases · Physics 2016-03-09 Soudabe Nasirimoghadam , Roohollah Aliabadi , Mohamad Ali Shahzamanian

The hydrodynamic regime of electron transport has been recently realized in conductors with ultra-low densities of defects. Although relaxation processes in two-dimensional (2D) fluids have been studied in many theoretical works, the…

Mesoscale and Nanoscale Physics · Physics 2021-01-04 P. S. Alekseev , A. P. Dmitriev

We confirm and expand on work by Chafin and Schaefer on hydrodynamic fluctuations in the unitary Fermi gas. Using the result for the equation of state from a recent MIT experiment, we derive lower bounds for \eta/n and \eta/s as a function…

Quantum Gases · Physics 2013-05-17 Paul Romatschke , Ryan Edward Young

The dilute Fermi gas at unitarity is scale invariant and its bulk viscosity vanishes. We compute the leading contribution to the bulk viscosity when the scattering length is not infinite. A measure of scale breaking is provided by the ratio…

Quantum Gases · Physics 2013-05-22 Thomas Schaefer , Kevin Dusling

The bulk viscosity determines dissipation during hydrodynamic expansion. It vanishes in scale invariant fluids, while a nonzero value quantifies the deviation from scale invariance. For the dilute Fermi gas the bulk viscosity is given…

Quantum Gases · Physics 2019-11-20 Tilman Enss

We report a model-independent measurement of the entropy, energy, and critical temperature of a degenerate, strongly interacting Fermi gas of atoms. The total energy is determined from the mean square cloud size in the strongly interacting…

Other Condensed Matter · Physics 2009-03-24 L. Luo , B. Clancy , J. Joseph , J. Kinast , J. E. Thomas

Strongly interacting Fermi gasses at low density possess universal thermodynamic properties which have recently seen very precise $PVT$ measurements by a group at MIT. This group determined local thermodynamic properties of a system of…

Quantum Gases · Physics 2015-11-30 George Ruppeiner

A micro-electro-mechanical system vibrating in its shear mode was used to study the viscosity of normal liquid $^3$He from 20mK to 770mK at 3bar, 21bar, and 29bar. The damping coefficient of the oscillator was determined by frequency sweeps…

Other Condensed Matter · Physics 2016-07-13 M. Gonzalez , W. G. Jiang , P. Zheng , C. S. Barquist , H. B. Chan , Y. Lee

We compute the viscosity spectral function of the dilute Fermi gas for different values of the s-wave scattering length $a$, including the unitarity limit $a\to\infty$. We perform the calculation in kinetic theory by studying the response…

Quantum Gases · Physics 2015-05-20 J. Chao , M. Braby , T. Schaefer

The viscous and thermal relaxation rates of an interacting fermion gas are calculated as functions of temperature and scattering length, using a many-body scattering matrix which incorporates medium effects due to Fermi blocking of…

Statistical Mechanics · Physics 2009-11-11 G. M. Bruun , H. Smith

The Unitary Fermi Gas (UFG) is one of the most strongly interacting systems known to date, as it saturates the unitarity bound on the quantum mechanical scattering cross section. The UFG corresponds to a two-component Fermi gas in the limit…

High Energy Physics - Lattice · Physics 2011-11-04 Joaquín E. Drut , Timo A. Lähde , Timour Ten

We propose to use the energy absorption spectroscopy to measure the kinetic coefficients of unitary Fermi gases in a uniform potential. We show that in our scheme, the energy absorption spectrum is proportional to the dynamic structure…

Quantum Gases · Physics 2018-04-18 Pengfei Zhang , Zhenhua Yu

In the framework of irreversible thermodynamics, we studied the transport properties of QGP. Shear viscosity and non-equilibrium entropy density related to viscous process at finite density has been investigated in weakly coupled limit by…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hui Liu , Defu Hou , Jiarong Li

A strongly-attractive, two-component Fermi gas of atoms exhibits universal behavior and should be mechanically stable as a consequence of the quantum mechanical requirement of unitarity. This requirement limits the maximum attractive force…

Superconductivity · Physics 2009-11-07 M. E. Gehm , S. L. Hemmer , S. R. Granade , K. M. O'Hara , J. E. Thomas

Degenerate Fermi gases of atoms near a Feshbach resonance show universal thermodynamic properties, which are here calculated with the geometry of thermodynamics, and the thermodynamic curvature $R$. Unitary thermodynamics is expressed as…

Statistical Mechanics · Physics 2015-06-17 George Ruppeiner

From an extensive calculation of static properties of a trapped Fermi superfluid at zero temperature using a density-functional formulation, we demonstrate a universal behavior of its observables, such as energy, chemical potential, radius…

Other Condensed Matter · Physics 2009-11-13 S. K. Adhikari

In this letter we present a unified derivation of the pressure equation of states, thermodynamics and scaling functions for the one-dimensional (1D) strongly attractive Fermi gases with $SU(w)$ symmetry. These physical quantities provide a…

Quantum Gases · Physics 2017-09-06 Yi-Cong Yu , Xiwen Guan