Regensburg 2019 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 32: Spintronics

HL 32.2: Vortrag

Mittwoch, 3. April 2019, 15:15–15:30, H33

Investigation of spin-orbit interaction in the regime of the persistent spin helix — •Sven Gelfert¹, Christian Frankerl¹, Christian Reichl², Dieter Schuh¹, Gian Salis³, Werner Wegscheider², Dominique Bougeard¹, Tobias Korn¹, and Christian Schüller¹ — ¹Institut für Experimentelle und Angewandte Physik, University of Regensburg, 93040 Regensburg, Germany — ²Laboratory for Solid State Physics, ETH Zurich, 8093 Zurich, Switzerland — ³IBM Research-Zurich, 8803 Rüschlikon, Switzerland

In our experiments, low-energy intrasubband spin-density excitations (SDE) are driven by resonant inelastic light scattering experiments in 12-nm-wide (001)-oriented GaAs-AlGaAs single quantum wells with balanced Rashba and Dresselhaus spin-orbit interaction strengths. The resulting symmetry of the effective spin-orbit field supports the persistent spin helix. Spin-flip intrasubband SDE transitions in the conduction band show a highly anisotropic splitting and can be accessed by two different measurement geometries where a wave-vector transfer into the two-dimensional electron system is required. In backscattering and grazing incidence geometry we can precisely map the anisotropic spin splitting for arbitrary crystal directions by rotating the sample on a piezo-driven rotary stage. With external magnetic fields (up to 6 Tesla) a superposition of the intrinsic spin-orbit field and the external field occurs, which allows us to deduce the spin-orbit field strength, the electron g factor and the single-particle relaxation time from our observations.