arXiv 1801.080862018-01cond-mat.quant-gashep-thnucl-thquant-ph

Virial expansion for the Tan contact and Beth-Uhlenbeck formula from 2D SO(2,1) anomalies

Wilder S. Daza, Joaquín E. Drut, Chris L. Lin, Carlos R. Ordóñez

备注：: 9 pages, 2 figures
发表信息：: Phys. Rev. A 97, 033630 (2018)
DOI：: 10.1103/PhysRevA.97.033630

英文摘要：

The relationship between 2D $SO(2,1)$ conformal anomalies in nonrelativistic systems and the virial expansion is explored using recently developed path-integral methods. In the process, the Beth-Uhlenbeck formula for the shift of the second virial coefficient $δb_2$ is obtained, as well as a virial expansion for the Tan contact. A possible extension of these techniques for higher orders in the virial expansion is discussed.

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