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Pseudo-gap and spin polarization in a two-dimensional electron gas

V. Vyurkov·A. Vetrov·V. Ryzhii
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Abstract

Tunnelling density of states in the vicinity of Fermi level of a two-dimensional electron gas subjected to an external parallel and zeroth magnetic field is calculated. It reveals a pseudo-gap recently observed in the experiments. The gap originates in spin polarization of 2DEG. Non-monotonic dependence of energy on a Landau level filling factor (density) was obtained. It implies the tunneling current peculiarities at filling factors 1/2 and 1. The Ising-like model of the exchange interaction in 2DEG was exploited instead of the conventional one. It was crucial to achieve even a qualitative agreement with experimental data.

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V. Vyurkov, A. Vetrov, V. Ryzhii. 2003-07-11. Pseudo-gap and spin polarization in a two-dimensional electron gas. https://doi.org/10.1142/s0219581x03001747

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