RT Journal Article
T1 Understanding the UV luminescence of zinc germanate: the role of native defects
A1 Dolado Fernández, Jaime
A1 Martínez Casado, María Ruth
A1 Hidalgo Alcalde, Pedro
A1 Gutiérrez, Rafael
A1 Dianat, Arezoo
A1 Cuniberti, Gianaurelio
A1 Domínguez-Adame Acosta, Francisco
A1 Díaz García, Elena
A1 Méndez Martín, María Bianchi
AB Achieving efficient and stable ultraviolet emission is a challenging goal in optoelectronic devices. Herein, we investigate the UV luminescence of zinc germanate Zn_2GeO_4 microwires by means of photoluminescence measurements as a function of temperature and excitation conditions. The emitted UV light is composed of two bands (a broad one and a narrow one) associated with the native defects structure. In addition, with the aid of density functional theory (DFT) calculations, the energy positions of the electronic levels related to native defects in Zn_2GeO_4 have been calculated. In particular, our results support that zinc interstitials are the responsible for the narrow UV band, which is, in turn, split into two components with different temperature dependence behaviour. The origin of the two components is explained on the basis of the particular location of Zn_i in the lattice and agrees with DFT calculations. Furthermore, a kinetic luminescence model is proposed to ascertain the temperature evolution of this UV emission. These results pave the way to exploit defect engineering in achieving functional optoelectronic devices to operate in the UV region.
PB Pergamon-Elsevier Science Ltd
SN 1359-6454
YR 2020
FD 2020-09-01
LK https://hdl.handle.net/20.500.14352/6516
UL https://hdl.handle.net/20.500.14352/6516
LA eng
NO © 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.This work was supported by Ministerio de Ciencia, Innovacion y Universidades (Grants MAT2016-75955 and RTI2018-097195-B-I00) and Deutsche Forschungsgemeinschaft (Grant CU 44/47-1). R. M.-C. would like to thank Dr. Giuseppe Mallia for very useful discussions.
NO Ministerio de Economía y Competitividad (MINECO)
NO Ministerio de Ciencia e Innovación (MICINN)
NO Sociedad Alemana de Investigación (DFG)
DS Docta Complutense
RD 6 abr 2025