Landau Level Gap Reduction at Abrupt Edges

I. Bartos; B. Rosenstein

doi:10.1142/s0217984994001175

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Landau Level Gap Reduction at Abrupt Edges

I. Bartos·B. Rosenstein

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Abstract

For an electron localized near a finite rectangular step potential under strong magnetic field we found a profound local reduction of the gap between neighbouring Landau levels. We investigate under what conditions the effect persists when the barrier gets smoother. The conclusion is that to get a substantial gap reduction the barrier gradient has to be larger than $\hbarω_c/a_L$ ($a_L$ is the magnetic length). The sensitivity of the gap reduction is illustrated using tilted and multiple step barriers and finite stripe configurations.

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I. Bartos, B. Rosenstein. 1994-09-14. Landau Level Gap Reduction at Abrupt Edges. https://doi.org/10.1142/s0217984994001175

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