有限粒子数费米系统温度对顺磁性的影响

Effects of Temperatures and Particle Number on Pauli Paramagnetism of Fermi Gas

根据弱磁场中理想费米气体的粒子数N+的几率分布函数G(β,N+),运用理论解析与数值模拟相结合的方法,研究了有限粒子数理想费米系统的泡利顺磁性,给出了粒子数临界值和上界磁场的解析式,分析了温度和粒子数对顺磁性的影响.研究表明,温度趋于费米温度时,极限磁化率与平均磁化率的偏差减小;当温度高于费米温度时,极限磁化率与平均磁化率的偏差随温度的升高先增大后减小.

On the basis of the probability distribution function of particle number,the Pauli paramagnetism of an ideal Fermi gas with finite number of particles is investigated by using a combination of theoretical analysis and numerical simulation.The analytical expressions of critical value of particle number and upper magnetic field are given and the effects of temperature and particle number on the paramagnetism are analyzed.It is shown that,when the temperature is close towards Fermi temperature,the difference between limit magnetic susceptibility and average magnetic susceptibility decreases.When the temperature is higher than the Fermi temperature,the resulting difference between limit magnetic susceptibility and average magnetic susceptibility increases first and then decreases with the increase of temperature.