Pauli paramagnetism of an ideal Fermi gas within canonical ensemble

摘要

Thermodynamic properties of an ideal Fermi gas in a uniform external magnetic field are investigated within canonical ensemble. By using the saddle point method, a simple method is proposed to calculate the probability distribution function of the system. The probability distribution function is used to calculate the thermodynamic properties of the system, such as the average value and fluctuations of the net magnetic moment and susceptibility. For a finite number of fermions, through the analysis of the fluctuations, it is shown that the strength of the external magnetic field should be larger than a critical magnetic field strength to observe the phenomenon of Pauli paramagnetism. (C) 2003 Elsevier B.V. All rights reserved. [References: 5]