Quantum Well Based on Graphene and Narrow-Gap Semiconductors

TL;DR

This paper analyzes the energy spectrum of a graphene-based quantum well with narrow-gap semiconductors, revealing conditions for gapless modes, spin splitting, and optical transition rules, with implications for nanoelectronic applications.

Contribution

It introduces a detailed model of a graphene and narrow-gap semiconductor quantum well, highlighting the conditions for gapless modes and analyzing optical and spin properties.

Findings

Gapless mode appears only with inverted narrow-gap semiconductors.

Spin splitting is calculated for nonsymmetric wells considering graphene's properties.

Optical transitions occur only with parity conservation.

Abstract

We consider the energy spectrum of the planar quantum well which consisted of two ribbons of narrow-gap semiconductors and a graphene ribbon between ones. It is shown that the gapless mode appears only in case of inverted narrow-gap semiconductors. Spin splitting of the energy spectrum for a nonsymmetric quantum well is calculated taking into account a specificity of graphene. We investigate interface states and optical transitions. It is shown that the optical transitions are possible only with a conservation of a parity.