College Physics ›› 2021, Vol. 40 ›› Issue (2): 59-62.doi: 10.16854 /j.cnki.1000-0712.200139

Previous Articles     Next Articles

Generalized thermal wavelength: definition,significance and applications

LI Xin-yu,ZHANG Zi-yi,WANG Xin,LIU Quan-hui   

  1. School for Theoretical Physics,College of Physics and Electronics,Hunan University,Changsha,Hunan 410082,China
  • Received:2020-04-15 Revised:2020-06-01 Online:2021-02-20 Published:2021-03-02


Photon gas and highly degenerate quantum gases are not classical ideal gas at all,and each of them has its own mean momentum from which a generalized thermal wave length can be thus defined,and the usual thermal wave length is an irrelevant concept.For a non-degenerate system,this wave length converges to the usual thermal one form a matter particle.For a degenerate system,the dimension of thermodynamic system must be larger than this generalized thermal wavelength,which leads to a criterion on the minimum dimension of the thermodynamic system.For some typical systems,we use the criterion to give their minimum dimensions.

Key words: thermal wavelength, quantum gas, thermodynamic limit