Competition between paramagnetism and diamagnetism in charged Fermi gases

Xiaoling Jian; Jihong Qin; Qiang Gu

doi:10.1016/j.physleta.2010.04.027

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arXiv · 1006.5179

Competition between paramagnetism and diamagnetism in charged Fermi gases

Xiaoling Jian·Jihong Qin·Qiang Gu

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Abstract

The charged Fermi gas with a small Lande-factor $g$ is expected to be diamagnetic, while that with a larger $g$ could be paramagnetic. We calculate the critical value of the $g$-factor which separates the dia- and para-magnetic regions. In the weak-field limit, $g_{c}$ has the same value both at high and low temperatures, $g_{c}=1/\sqrt{12}$. Nevertheless, $g_{c}$ increases with the temperature reducing in finite magnetic fields. We also compare the $g_{c}$ value of Fermi gases with those of Boltzmann and Bose gases, supposing the particle has three Zeeman levels $σ=\pm1, 0$, and find that $g_{c}$ of Bose and Fermi gases is larger and smaller than that of Boltzmann gases, respectively.

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Xiaoling Jian, Jihong Qin, Qiang Gu. 2010-06-27. Competition between paramagnetism and diamagnetism in charged Fermi gases. https://doi.org/10.1016/j.physleta.2010.04.027

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