Heterostructures from two-dimensional transition-metal dichalcogenides MX_2 have emerged as a hot topic in recent years due to their various fascinating properties. Here, we investigated the temperature dependent Rama...Heterostructures from two-dimensional transition-metal dichalcogenides MX_2 have emerged as a hot topic in recent years due to their various fascinating properties. Here, we investigated the temperature dependent Raman and photoluminescence(PL) spectra in vertical stacked WS_2/MoS_2 monolayer heterostructures. Our result shows that both E_(2g)~1 and A_(1g) modes of WS_2 and MoS_2 vary linearly with temperature increasing from 300 to 642 K. The PL measurement also reveals strong temperature dependencies of the PL intensity and peak position. The activation energy of the thermal quenching of the PL emission has been found to be equal to 69.6 meV. The temperature dependence of the peak energy well follows the bandgap shrinkage of bulk semiconductor.展开更多
基金supported by the National Basic Research Program of China (2015CB932403)the National Natural Science Foundation of China (11674012, 61422501, 11374023, 11304054 and 61521004)+2 种基金Beijing Natural Science Foundation (L140007)Foundation for the Author of National Excellent Doctoral Dissertation of China (201420)National Program for Support of Top-notch Young Professionals
文摘Heterostructures from two-dimensional transition-metal dichalcogenides MX_2 have emerged as a hot topic in recent years due to their various fascinating properties. Here, we investigated the temperature dependent Raman and photoluminescence(PL) spectra in vertical stacked WS_2/MoS_2 monolayer heterostructures. Our result shows that both E_(2g)~1 and A_(1g) modes of WS_2 and MoS_2 vary linearly with temperature increasing from 300 to 642 K. The PL measurement also reveals strong temperature dependencies of the PL intensity and peak position. The activation energy of the thermal quenching of the PL emission has been found to be equal to 69.6 meV. The temperature dependence of the peak energy well follows the bandgap shrinkage of bulk semiconductor.