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Multi-band energy spectra of spin-1/2 electrons with two-dimensional magnetic modulations

Ming-Che Chang·Min-Fong Yang
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Abstract

The energy spectra of spin-1/2 electrons under two-dimensional magnetic field modulations are calculated beyond the one-band approximation. Our formulation is generally applicable to a modulation field with a rectangular lattice symmetry. The field distribution within a plaquette is otherwise arbitrary. The spectra being obtained are qualitatively different from their electric modulated counterparts. Peculiar features of the spectra are that, for an electron with a g factor precisely being equal to two, no matter how strong the modulation is, the zero-energy level seems to be unaffected by the modulation and is separated from higher energy levels with a nonzero energy gap. Moreover, there is a two-fold degenerancy for all states with positive energies with respect to spin flip. These features agree with earlier analytical studies of the periodically magnetic modulated systems.

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Ming-Che Chang, Min-Fong Yang. 1997-11-24. Multi-band energy spectra of spin-1/2 electrons with two-dimensional magnetic modulations. https://doi.org/10.1103/physrevb.57.13002

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