Mechanical exfoliation(ME) and chemical vapor deposition(CVD) MoS2 monolayers have been extensively studied, but the large differences of nonlinear optical performance between them have never been clarified. Here,we p...Mechanical exfoliation(ME) and chemical vapor deposition(CVD) MoS2 monolayers have been extensively studied, but the large differences of nonlinear optical performance between them have never been clarified. Here,we prepared MoS2 monolayers using ME and CVD methods and investigated the two-photon absorption(TPA)response and its saturation. We found that the TPA coefficient of the ME monolayer was about(1.88 ± 0.21)× 10^3 cm/GW, nearly two times that of the CVD one at(1.04 ± 0.15)× 10^3 cm/GW. Furthermore,we simulated and compared the TPA-induced optical pulse modulation in multilayer cascaded structures, which is instructive and meaningful for the design of optical devices such as a beam shaper and optical limiter.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.61675217 and 11874370)the Strategic Priority Research Program of CAS(No.XDB16030700)+4 种基金the Key Research Program of Frontier Science of CAS(No.QYZDB-SSW-JSC041)the Program of Shanghai Academic Research Leader(No.17XD1403900)the Natural Science Foundation of Shanghai(No.18ZR1444700)the Shanghai Rising-Star Program(A Type 19QA1410000)the Youth Innovation Promotion Association,CAS
文摘Mechanical exfoliation(ME) and chemical vapor deposition(CVD) MoS2 monolayers have been extensively studied, but the large differences of nonlinear optical performance between them have never been clarified. Here,we prepared MoS2 monolayers using ME and CVD methods and investigated the two-photon absorption(TPA)response and its saturation. We found that the TPA coefficient of the ME monolayer was about(1.88 ± 0.21)× 10^3 cm/GW, nearly two times that of the CVD one at(1.04 ± 0.15)× 10^3 cm/GW. Furthermore,we simulated and compared the TPA-induced optical pulse modulation in multilayer cascaded structures, which is instructive and meaningful for the design of optical devices such as a beam shaper and optical limiter.