Regensburg 2019 – wissenschaftliches Programm
HL 27.7: Vortrag
Mittwoch, 3. April 2019, 11:15–11:30, H36
excitons localized by physisorbed gas molecules in MoSe2 monolayer — •Tommaso Venanzi1,2, Stephan Winnerl1, Alexej Pashkin1, Manfred Helm1,2, and Harald Schneider1 — 1Helmholtz-Zentrum Dresden-Rossendorf, 01314 Dresden, Germany — 2Technische Universität Dresden, 01062 Dresden, Germany
In the study of 2D materials an extremely relevant topic is the presence of defects. We have studied excitons localized by physisorbed gas molecules in MoSe2 monolayer by means of low-temperature photoluminescence. We have investigated how the localized exciton depends on temperature taking care of the effects of laser irradiation. We observe a red-shift of the photoluminescence peak with temperature that is not only addressable to renormalization of the bandgap or thermal instability of the localization. On the other hand we observe a blue-shift of the peak when increasing the laser irradiation dose. Finally we propose a physical mechanism that can explain our experimental observations.