Eu-Mg defects and donor-acceptor pairs in GaN: photodissociation and the excitation transfer problem
Eu-Mg defects and donor-acceptor pairs in GaN: photodissociation and the excitation transfer problem
复制标题
DOI：
10.1088/1361-6463/aaa1cc
复制
发表时间：
2018-02-14
影响因子：
3.4
通讯作者：
Bockowski, M.
中科院分区：
文献类型：
--
作者：
Singh, A. K.;O'Donnell, K. P.;Bockowski, M.
研究了掺Mg的HVPE生长的GaN体材料中Eu ~（3+）离子注入的温度依赖性光致发光（TDPL）曲线，以及GaN（Mg）（未注入）和GaN（Mg）：Eu样品中浅Mg受主的施主-受主对（DAP）的温度依赖性光致发光（TDPL）曲线。在125 K以下，Eu ~（3+）在GaN（Mg）：Eu中的TDPL与DAP的TDPL相关。低于75 K时，Eu 3+发射的强度饱和，表明可用于接收从宿主转移的激发的Eu-Mg缺陷的数量有限，而DAP继续增加，尽管在注入样品中比未注入样品更慢。在低温下长时间暴露于UV光导致Eu-Mg缺陷在其Eu 1（Mg）构型中的光解离，浅DAP发射相应增加，并且出现来自未缔合的Eu-Ga（Eu 2）缺陷的发射。
We have investigated the temperature-dependent photoluminescence (TDPL) profiles of Eu3+ ions implanted in an HVPE-grown bulk GaN sample doped with Mg and of donor-acceptor pairs (DAP) involving the shallow Mg acceptor in GaN(Mg) (unimplanted) and GaN(Mg): Eu samples. Below 125 K, the TDPL of Eu3+ in GaN(Mg): Eu correlates with that of the DAP. Below 75 K, the intensity of Eu3+ emission saturates, indicating a limitation to the numbers of Eu-Mg defects available to receive excitation transferred from the host, while the DAP continues to increase, albeit more slowly in the implanted than the unimplanted sample. Prolonged exposure to UV light at low temperature results in the photodissociation of Eu-Mg defects in their Eu1(Mg) configuration, with a corresponding increase in shallow DAP emission and the emergence of emission from unassociated Eu-Ga (Eu2) defects.