Understanding the role of facets and twin defects in the optical performance of GaAs nanowires for laser applications

Date

2021

Authors

Azimi, Zahra
Gagrani, Nikita
Qu, Jiangtao
Lee Cheong Lem, Olivier
Mokkapati, Sudha
Cairney, Julie
Zheng, Rongkun
Tan, Hark Hoe
Jagadish, Chennupati
Wong-Leung, Jennifer

Journal Title

Journal ISSN

Volume Title

Publisher

Royal Society of Chemistry

Abstract

GaAs nanowires are regarded as promising building blocks of future optoelectronic devices. Despite progress, the growth of high optical quality GaAs nanowires is a standing challenge. Understanding the role of twin defects and nanowire facets on the optical emission and minority carrier lifetime of GaAs nanowires is key for the engineering of their optoelectronic properties. Here, we present new insights into the microstructural parameters controlling the optical properties of GaAs nanowires, grown via selective-area metal-organic vapor-phase epitaxy. We observe that these GaAs nanowires have a twinned zinc blende crystal structure with taper-free {110} side facets that result in an ultra-low surface recombination velocity of 3.5 × 104 cm s-1. This is an order of magnitude lower than that reported for defect-free GaAs nanowires grown by the vapor-liquid-solid technique. Using time-resolved photoluminescence and cathodoluminescence measurements, we untangle the local correlation between structural and optical properties demonstrating the superior role of the side facets in determining recombination rates over that played by twin defects. The low surface recombination velocity of these taper-free {110} side facets enable us to demonstrate, for the first time, low-temperature lasing from bare (unpassivated) GaAs nanowires, and also efficient room-temperature lasing after passivation with an AlGaAs shell.

Description

Keywords

Citation

Source

Nanoscale Horizons

Type

Journal article

Book Title

Entity type

Access Statement

License Rights

DOI

10.1039/d1nh00079a

Restricted until

2099-12-31