Regensburg 2016 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HL: Fachverband Halbleiterphysik

HL 52: Spintronics (incl. quantum dynamics) (Joint session of HL, MA and TT, organized by MA)

HL 52.7: Talk

Wednesday, March 9, 2016, 11:15–11:30, H32

Ultra-long electron and hole spin lifetimes in monolayer WSe₂ — Sammy Pissinger, •Robin de Winter, Christopher Franzen, Manfred Ersfeld, Sebastian Kuhlen, Christoph Stampfer, and Bernd Beschoten — 2nd Institute of Physics and JARA-FIT, RWTH Aachen University, Germany

There is strong interest in optical generation and detection of valley spin polarizations in transition metal dichalcogenides. We report on time-resolved two color pump probe Kerr rotation measurements on mechanically exfoliated monolayer WSe₂ crystals. We find electron and hole spin lifetimes of up to 100 ns at low temperatures. These values are in good agreement with exciton lifetimes extracted from all-optical time-resolved reflectivity indicating that the spin lifetimes are limited by exciton recombination times in our crystals. Electron spin precession in Voigt geometry furthermore reveals inhomogeneous spin dephasing caused by a large spread in the local g factors.