Quantum confinement effects in InAs-InP core-shell nanowires

TL;DR

This study demonstrates quantum confinement effects in single InAs-InP core-shell nanowires, revealing quantized energy levels through emission spectra and theoretical modeling, advancing understanding of nanoscale semiconductor structures.

Contribution

First observation of quantum confinement in InAs-InP nanowires with combined experimental photoluminescence and theoretical analysis.

Findings

Identification of emission peaks from ground and excited states

Good agreement between experimental data and theoretical calculations

Insights into strain and structural effects on quantum confinement

Abstract

We report the detection of quantum confinement in single InAs-InP core-shell nanowires. The wires having an InAs core with ~25 nm diameter are characterized by emission spectra in which two peaks are identified under high excitation intensity conditions. The peaks are caused by emission from the ground and excited quantized levels, due to the quantum confinement in the plane perpendicular to the nanowire axis. We have identified in the emission spectra different energy contributions related to the wurtzite structure of the wires, the strain between the wurtzite core and shell, and the confinement energy of the InAs core. Calculations based on 6-band strain-dependent k.p theory allow the theoretical estimation of the confined energy states in such materials and we found these results to be in good agreement with those from the photoluminescence studies.