强磁场中Fermi气体的稳定性及顺磁性  

The stability and paramagnetism of Fermi gas in a strong magnetic field

作　　者：门福殿 王海堂 何晓刚 

机构地区：[1]中国石油大学(华东)理学院,青岛266555

出　　处：《物理学报》2012年第10期38-42,共5页Acta Physica Sinica

基　　金：山东省自然科学基金(批准号:ZR2010AL027);中央高校基本科研业务费专项资金(批准号:10CX04039A)资助的课题~~

摘　　要：运用理论解析和数值模拟的方法,研究强磁场中Fermi气体在低温下的稳定性及顺磁性,分析温度、磁场对稳定性及磁化率的影响.研究结果显示,强磁场引起系统稳定性的改变,这种改变与温度有关,而温度对稳定性改变及磁化率的影响又与自由气体的化学势即粒子数密度有关.当自由系统的化学势为偶数时,磁场弱化系统的稳定性,温度升高可降低系统的磁化率;当自由系统的化学势为奇数时,磁场强化系统的稳定性,温度升高可增大系统的磁化率.升高温度,可以弱化磁场对系统稳定性的影响;加强磁场,可以使得系统稳定性的改变发生振荡,使系统磁化率的振荡中心下移.By using theoretical analysis and numerical simulation, the stability and the paramagnetism of Fermi gas in a strong magnetic field at low temperatures are studied, and the influences of temperature and magnetic field on the stability and susceptibility of the system are analyzed. The results show that the strong magnetic field causes variation of a system stability, and such a change relates to temperature. While the effects of temperature on stability and susceptibility are relevant to the chemical potential （i.e. the particle number density） of free gas. When the chemical potential is even, the magnetic field weakens the stability of the system, and the increasing of temperature leads to the reduction in the susceptibility of the system. When the chemical potential is odd, the magnetic field strengthens the stability of the system, while the increasing of temperature can increase the susceptibility of the system. With temperature increasing, the effect of the magnetic field on the stability is weakened. With magnetic field increasing, the change of the stability of the system becomes oscillatory, and the oscillation center of the susceptibility shifts down.

关 键 词：强磁场 Fermi气体 稳定性 磁化率 

分 类 号：O562[理学—原子与分子物理]