Growth of Topological Insulator Bi2Se3 Particles on GaAs via Droplet Epitaxy

TL;DR

This paper reports the growth of Bi2Se3 topological insulator nanoparticles on GaAs substrates using droplet epitaxy, demonstrating control over their size, height, and density, which is promising for quantum computing applications.

Contribution

It introduces a method to grow and control Bi2Se3 topological insulator nanoparticles on GaAs using droplet epitaxy, enabling potential quantum device applications.

Findings

Nanoparticles ranged from 5-15 nm in height.

Controlled nanoparticle density via substrate temperature and bismuth deposition.

Size and density tunability demonstrated within the growth parameters.

Abstract

The discovery of topological insulators (TIs) and their unique electronic properties has motivated research into a variety of applications, including quantum computing. It has been proposed that TI surface states will be energetically discretized in a quantum dot nanoparticle. These discretized states could then be used as basis states for a qubit that is more resistant to decoherence. In this work, prototypical TI Bi2Se3 nanoparticles are grown on GaAs (001) using the droplet epitaxy technique, and we demonstrate the control of nanoparticle height, area, and density by changing the duration of bismuth deposition and substrate temperature. Within the growth window studied, nanoparticles ranged from 5-15 nm tall with an 8-18nm equivalent circular radius, and the density could be relatively well controlled by changing the substrate temperature and bismuth deposition time.