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arXiv · 1004.5390

S-matrix approach to quantum gases in the unitary limit II: the three-dimensional case

Pye-Ton How·André LeClair
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Abstract

A new analytic treatment of three-dimensional homogeneous Bose and Fermi gases in the unitary limit of negative infinite scattering length is presented, based on the S-matrix approach to statistical mechanics we recently developed. The unitary limit occurs at a fixed point of the renormalization group with dynamical exponent z=2 where the S-matrix equals -1. For fermions we find T_c /T_F is approximately 0.1. For bosons we present evidence that the gas does not collapse, but rather has a critical point that is a strongly interacting form of Bose-Einstein condensation. This bosonic critical point occurs at n lambda^3 approximately 1.3 where n is the density and lambda the thermal wavelength, which is lower than the ideal gas value of 2.61.

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Pye-Ton How, André LeClair. 2010-04-29. S-matrix approach to quantum gases in the unitary limit II: the three-dimensional case. https://doi.org/10.1088/1742-5468%2F2010%2F07%2Fp07001

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