FIBONACCI SUPERLATTICES OF NARROW-GAP III-V SEMICONDUCTORS

TL;DR

This paper presents a theoretical study of Fibonacci superlattices made from narrow-gap III-V semiconductors, revealing self-similar energy spectra and analyzing electronic transport properties related to quasiperiodicity.

Contribution

It introduces a detailed theoretical model for Fibonacci superlattices of III-V semiconductors, including electronic structure and transport properties, using transfer-matrix techniques.

Findings

Self-similar electronic spectra observed in Fibonacci superlattices.

Transport properties linked to spatial localization of electronic states.

Application to InAs/GaSb superlattices demonstrates the model's relevance.

Abstract

We report theoretical electronic structure of Fibonacci superlattices of narrow-gap III-V semiconductors. Electron dynamics is accurately described within the envelope-function approximation in a two-band model. Quasiperiodicity is introduced by considering two different III-V semiconductor layers and arranging them according to the Fibonacci series along the growth direction. The resulting energy spectrum is then found by solving exactly the corresponding effective-mass (Dirac-like) wave equation using tranfer-matrix techniques. We find that a self-similar electronic spectrum can be seen in the band structure. Electronic transport properties of samples are also studied and related to the degree of spatial localization of electronic envelope-functions via Landauer resistance and Lyapunov coefficient. As a working example, we consider type II InAs/GaSb superlattices and discuss in detail our results in this system.