Communications in Theoretical Physics ›› 2021, Vol. 73 ›› Issue (6): 065602. doi: 10.1088/1572-9494/abf4b6

• Statistical Physics, Soft Matter and Biophysics • Previous Articles     Next Articles

Padé approximant approach to singular properties of quantum gases: the ideal cases

Yuan-Hong Tian(田远鸿)1,Wen-Du Li(李文都)2,(),Yao Shen(沈尧)3,(),Wu-Sheng Dai(戴伍圣)1,()   

  1. 1Department of Physics, Tianjin University, Tianjin 300350, China
    2College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387, China
    3School of Criminal Investigation and Forensic Science, People’s Public Security University of China, Beijing 100038, China
  • Received: 2021-01-29 Revised: 2021-03-31 Accepted: 2021-04-03 Published: 2021-06-01
  • Contact: Wu-Sheng Dai(戴伍圣) E-mail:liwendu@tjnu.edu.cn;shenyaophysics@hotmail.com;daiwusheng@tju.edu.cn

Abstract:

In this paper, we show how to recover the low-temperature and high-density information of ideal quantum gases from the high-temperature and low-density approximation by the Padé approximant. The virial expansion is a high-temperature and low-density expansion and in practice, often, only the first several virial coefficients can be obtained. For Bose gases, we determine the BEC phase transition from a truncated virial expansion. For Fermi gases, we recover the low-temperature and high-density result from the virial expansion.

Key words: approximate analytic continuation, virial expansion, Padé, approximant, quantum gas