Regensburg 2022 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 25: Poster 1
HL 25.29: Poster
Mittwoch, 7. September 2022, 18:00–20:00, P2
Ultrafast dynamics of dark states in photocurrent of TMD heterostructures — •Denis Yagodkin, Elias Ankerhold, Abhijeet Kumar, Johanna Richter, Firas Ben Moussa, Cornelius Gahl, and Kirill Bolotin — Freie Universitat Berlin
We study the photocurrent response of TMD heterostructures MoS2/MoSe2 with 150 femtosecond time resolution. In order to study the dynamics of transport at the interface of the heterostructure, we tune one pulse to MoS2 excitation resonance and the second, time-delayed pulse, to that of MoSe2. We find stark asymmetry between negative and positive delays. We attribute this asymmetry to the formation of interlayer excitons. Using a simple model of charge carriers decaying in optically dark states we successfully describe both time-resolved reflectivity and photocurrent response of heterostructures. Extracted formation time of interlayer excitons is similar to that observed in ARPES and TR-THz at room temperature. Strong response to interlayer excitons shows the potential of our technique in detecting other dark states promising for information storing and processing.