Coherent Heteroepitaxy of Bi2Se3 on GaAs (111)B

TL;DR

This paper demonstrates the successful heteroepitaxial growth of high-quality Bi2Se3 thin films on GaAs (111)B substrates, achieving atomically sharp interfaces and flat terraces, enabling future spin dynamics studies.

Contribution

It reports a novel method for growing coherent Bi2Se3 films on GaAs with atomically sharp interfaces and flat terraces, advancing topological insulator integration.

Findings

Bi2Se3 grows highly c-axis oriented on GaAs (111)B

Achieved atomically sharp interface and flat terraces

Initial Kerr rotation measurements indicate potential for spin dynamics studies

Abstract

We report the heteroepitaxy of single crystal thin films of Bi2Se3 on the (111)B surface of GaAs by molecular beam epitaxy. We find that Bi2Se3 grows highly c-axis oriented, with an atomically sharp interface with the GaAs substrate. By optimizing the growth of a very thin GaAs buffer layer before growing the Bi2Se3, we demonstrate the growth of thin films with atomically flat terraces over hundreds of nanometers. Initial time-resolved Kerr rotation measurements herald opportunities for probing coherent spin dynamics at the interface between a candidate topological insulator and a large class of GaAs-based heterostructures.