Raman sensitivity to crystal structure in InAs nanowires

TL;DR

This study uses temperature-dependent Raman spectroscopy combined with electron transmission to analyze how crystal structure variations in InAs nanowires affect phonon energies and linewidths, revealing insights into phase composition and interfacial strain.

Contribution

It introduces a non-invasive Raman method to determine crystal phase fractions and interfacial strain in InAs nanowires based on temperature-dependent phonon behavior.

Findings

Temperature-dependent phonon energies indicate phase composition.

Phonon linewidths reveal interfacial strain effects.

Raman spectroscopy provides a non-invasive way to study polytypism.

Abstract

We report a combined electron transmission and Raman spectroscopy study of InAs nanowires. We demonstrate that the temperature dependent behavior of optical phonon energies can be used to determine the relative wurtzite fraction in the InAs nanowires. Furthermore, we propose that the interfacial strain between zincblende and wurtzite phases along the length of the wires manifests in the temperature-evolution of the phonon linewidths. From these studies, temperature-dependent Raman measurements emerge has a non-invasive method to study polytypism in such nanowires.