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Butterfly-like spectra and collective modes of antidot superlattices in magnetic fields

Egidijus Anisimovas·Peter Johansson
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Abstract

We calculate the energy band structure for electrons in an external periodic potential combined with a perpendicular magnetic field. Electron-electron interactions are included within a Hartree approximation. The calculated energy spectra display a considerable degree of self-similarity, just as the ``Hofstadter butterfly.'' However, screening affects the butterfly, most importantly the bandwidths oscillate with magnetic field in a characteristic way. We also investigate the dynamic response of the electron system in the far-infrared (FIR) regime. Some of the peaks in the FIR absorption spectra can be interpreted mainly in semiclassical terms, while others originate from inter(sub)band transitions.

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Egidijus Anisimovas, Peter Johansson. 1999-07-07. Butterfly-like spectra and collective modes of antidot superlattices in magnetic fields. https://doi.org/10.1103/physrevb.60.7744

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