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arXiv · 1001.3061

The metal-insulator transition and lattice distortion in semiconductors

Fedor V. Prigara
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Abstract

A relation between the energy of an elementary `insulating' excitation corresponding to the metal-insulator transition and the bandgap width in a semiconductor is obtained. An effect of atomic relaxation on the temperature and pressure dependence of the bandgap width is considered. It is shown that the metal-insulator transition in a semiconductor causes a weak rhombohedral or monoclinic distortion in the case of a diamond and zincblende structure and a weak tetragonal or orthorhombic distortion in the case of a rocksalt structure. A change in the bandgap associated with a ferroelectric (antiferroelectric) transition in a semiconductor is also obtained.

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Fedor V. Prigara. 2010-03-01. The metal-insulator transition and lattice distortion in semiconductors. https://arxiv.org/abs/1001.3061

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