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arXiv · 1909.12293

Dirac energy spectrum and inverted band gap in metamorphic InAsSb/InSb superlattices

Sergey Suchalkin·Maksim Ermolaev·Tonica Valla·Gela Kipshidze·Dmitry Smirnov·Seongphill Moon·Mykhaylo Ozerov·Zhigang Jiang·Yuxuan Jiang·Stefan P. Svensson·Wendy L. Sarney·Gregory Belenky
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Abstract

A Dirac-type energy spectrum was demonstrated in gapless ultra-short-period metamorphic InAsSb/InSb superlattices by angle-resolved photoemission spectroscopy (ARPES_ measurements. The Fermi velocity value 7.4x10^5 m/s in a gapless superlattice with a period of 6.2nm is in a good agreement with the results of magneto-absorption experiments. An "inverted" bandgap opens in the center of the Brillouin zone at higher temperatures and in the SL with a larger period. The ARPES data indicate the presence of a surface electron accumulation layer

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Sergey Suchalkin, Maksim Ermolaev, Tonica Valla, Gela Kipshidze, Dmitry Smirnov, Seongphill Moon, Mykhaylo Ozerov, Zhigang Jiang, Yuxuan Jiang, Stefan P. Svensson, Wendy L. Sarney, Gregory Belenky. 2019-09-26. Dirac energy spectrum and inverted band gap in metamorphic InAsSb/InSb superlattices. https://doi.org/10.1063/1.5128634

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