Quantum Emitters Induced by High Pressure and UV Laser Irradiation in Multilayer GaSe

Published

February 14, 2025

Author(s)

Sinto Varghese, Sichenge Wang, Bimal Neupane, Bhojraj Bhandari, Yan Jiang, Roberto Gonzalez Rodriguez, Sergiy Krylyuk, Albert Davydov, Hao Yan, Yuanxi Wang, Anupama Kaul, Jingbiao Cui, Yuankun Lin

Abstract

In this work, we report on defect generation in multilayer GaSe through hydrostatic pressure quenching and UV laser irradiation. The Raman line width from the UV 266 nm irradiated sample is much wider than that in pressure-quenched GaSe, corresponding to a wider defect energy distribution range in the former sample than the latter. After quenching from 11.2 GPa, three photoluminescence (PL) peaks from defect states are observed at 657, 681, and 695 nm at a low temperature of 93 K. Defect-related peaks at 649, 694, 750, and 774 nm also appear in low-temperature PL spectra after UV laser irradiation, with a nonmonotonous intensity dependence on irradiation duration. There are common features in defects produced by these two methods: the PL peaks with the lowest energy are sharp, and their PL intensities increase linearly with the excitation laser power and saturate above a certain excitation laser power. These two features are similar to those in defects for single-photon emission (SPE) in other 2D materials at even lower temperatures. Fluorescence lifetime imaging shows distinguished short (2.3 ns) and long (75.6 nm) lifetimes of the 695 nm PL line in pressure-quenched GaSe. The density functional theory predicts defect energy levels related to Se vacancy.

Citation

ACS Ω

Volume

10

Issue

7

Pub Type

Journals

Download Paper

https://doi.org/10.1021/acsomega.5c00680

Local Download

Keywords

2D materials, GaSe, defects generation, photoluminescence

Citation

Varghese, S. , Wang, S. , Neupane, B. , Bhandari, B. , Jiang, Y. , Gonzalez Rodriguez, R. , Krylyuk, S. , Davydov, A. , Yan, H. , Wang, Y. , Kaul, A. , Cui, J. and Lin, Y. (2025), Quantum Emitters Induced by High Pressure and UV Laser Irradiation in Multilayer GaSe, ACS Ω, [online], https://doi.org/10.1021/acsomega.5c00680, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=959402 (Accessed April 10, 2025)