反常磁矩对弱磁场弱相互作用费米气体热力学性质的影响

Effect of anomalous magnetic moment on thermodynamic properties of weakly interacting Fermi gas in weak magnetic field

考虑费米子的反常磁矩,运用赝势法和热力学理论,导出弱磁场中弱相互作用费米气体自由能的解析式,以此为基础给出高温和低温情况下系统热力学性质,分析反常磁矩对热力学性质的影响机理.研究表明:反常磁矩对热力学性质的影响与温度相关,而且这种影响随温度的上升在低温区是增大的,在高温区是减小的;对于系统的化学势、内能,反常磁矩加强了磁场的影响,弱化了相互作用的影响;对于系统的热容量,反常磁矩在低温区使其减小,在高温区使其增加.

Taking the anomalous magnetic moment into consideration, the analytical expression of the free energy for a weakly interacting Fermi gas in a weak magnetic field is derived by using the pseudopotential method and thermodynamic theory, therefore the thermodynamic properties can be studied. Based on the derived expression, the thermodynamic properties of this system at both high and low temperatures are given, and the effect of anomalous magnetic moment on thermodynamic properties can be analyzed. The effect of anomalous magnetic moment on the thermodynamic properties is related to temperature, and with the rise of temperature this effect increases in the low temperature zone, but decreases in the high temperature zone. For the chemical potential and internal energy of the system, the anomalous magnetic moment strengthens the influence of the magnetic field, but weakens the influence of the interaction. Under the influence of anomalous magnetic moment, the heat capacity of the system decreases in the low temperature zone, but increases in the high temperature zone.