Phonon-assisted Upconversion Photoluminescence in Monolayer MoSe 2 and WSe 2
Xu Weigao, Zhao Yanyuan, Shen Chao, Zhang Jun, Xiong Qihua
Acta Chim. Sinica . 2015, (9): 959 -964 .  DOI: 10.6023/A15030216