Optical and defect properties of S-doped and Al-doped GaSe crystals
Huang Chang-Bao, WuWu Hai-Xin †, Ni You-Bao, Wang Zhen-You, Chen Shi-Jing
       

PL spectra of (a) pure, (b) Al-doped, and (c) S-doped GaSe crystals at 78 K.