Giant enhancement of photoluminescence emission in monolayer WS_(2)by femtosecond laser irradiation  

作　　者：Cheng-Bing Qin Xi-Long Liang Shuang-Ping Han Guo-Feng Zhang Rui-Yun Chen Jian-Yong Hu Lian-Tuan Xiao Suo-Tang Jia 

机构地区：[1]State Key Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Laser Spectroscopy,Shanxi University,Taiyuan 030006,China [2]Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan 030006,China

出　　处：《Frontiers of physics》2021年第1期143-150,共8页物理学前沿（英文版）

基　　金：supported by the National Key Research and Development Program of China(Grant No.2017YFA0304203);the National Natural Science Foundation of China(Nos.91950109,61875109,61527824,61675119);the Natural Science Foundation of Shanxi Province(No.201901D111010(ZD)),PCSIRT(No.IRT_17R70),1331KSC,PTIT;Postgraduate Education Innovation Project of Shanxi Province(Nos.2019SY052,2020BY022).

摘　　要：Monolayer transition metal dichalcogenides have emerged as promising mat erials for opt oelectTonic and nanophotonic devices.However,the low photoluminescence(PL)quantum yield(QY)hinders their various potential applications.Here we engineer and enhance the PL intensity of monolayer WS_(2)by femtosecond laser irradiation.More than two orders of magnitude enhancement of PL intensity as compared to the as-prepared sample is determined.Furthermore,the engineering time is shortened by three orders of magnitude as compared to the improvement of PL intensity by continuous-wave laser irradiation.Based on the evolution of PL spectra,we attribute the giant PL enhancement to the conversion from trion emission to exciton,as well as the improvement of the QY when exciton and trion are localized to the new-formed defects.We have created microstructures on the monolayer WS_(2)based on the enhancement of PL intensity,where the engineered structures can be stably stored for more than three years.This flexible approach with the feature of excellent long-term storage stability is promising for applications in information storage,display technology,and opto electronic devices.

关 键 词：monolayers WS_(2) giant enhancement PHOTOLUMINESCENCE femtosecond laser irradiation MICROPATTERNING exciton TRION quantum yield 

分 类 号：O43[机械工程—光学工程]