二维含铁磁耦合费米气体磁学性质的研究

Magnetic properties of two-dimensional Fermi gases with ferromagnetic interaction

在平均场理论的框架下,推导出外磁场中具有铁磁耦和作用的二维费米气体的自洽方程,在此基础上,运用量子统计力学研究系统的磁学性质.结果表明总磁化强度密度随磁场强度的增大会出现极大值点,且随铁磁耦合强度增大,极大值点向磁场减弱的方向移动.总磁化强度密度也随Lande因子的增大,发生由抗磁性向顺磁性的转变.

Mean-field self-consistent equations of two-dimensional spin-1/2 Fermi gases with ferromagnetic interaction are derived within the mean-field theory. Magnetic properties are then investigated through quantum statistics. Paramagnetism and diamagnetism are found to compete with each other with increasing Lande- factor. With increasing magnetic field intensity, magnetization intensity increases until a maximum value point appears. With increasing ferromagnetic coupling, the maximum point moves toward the direction of weakening magnetic field. With increasing Lande-factor, transition from diamagnetism to paramagnetism is observed.