Dipole Orientation Shift of Ga2Se2 by Quantum Confinement

Ke Xiao; Tengfei Yan; Xiaodong Cui

doi:10.1021/acsnano.9b08524

Dipole Orientation Shift of Ga₂Se₂ by Quantum Confinement

ACS Nano. 2020 Jan 28;14(1):1027-1032. doi: 10.1021/acsnano.9b08524. Epub 2019 Dec 19.

Authors

Ke Xiao¹, Tengfei Yan¹, Xiaodong Cui¹

Affiliation

¹ Department of Physics , University of Hong Kong , Hong Kong , China.

PMID: 31799830
DOI: 10.1021/acsnano.9b08524

Abstract

In the family of III-VI monochalcogenides M₂X₂ (M = gallium, indium; X = sulfur, selenide, etc.), the interlayer interaction and the electronic band edges share the contribution of the same chalcogenide atomic orbits. This makes quantum confinement and interlayer interaction play a subtle role in two-dimensional (2D) monochalcogenides crystals. In this report, we study the direction-resolved photoluminescence of 2D Ga₂Se₂ at various thicknesses. We observe that the in-plane dipole radiation survives, but out-of-plane dipole radiation fades at 2D limits.

Keywords: Ga2Se2; dipole orientation; interlayer coupling; monochalcogenides; quantum confinement; two-dimensional semiconductor.