Optically induced non-equilibrium spin transport in mesoscopic semiconductor circuits

• Antragsteller: Professor Dr. Alexander Walter Holleitner
• Fachliche Zuordnung: Experimentelle Physik der kondensierten Materie
• Förderung: Förderung von 2007 bis 2015
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 40915753

Mesoscopic semiconductor circuits shall be systematically characterized and explored to enable an efficient information processing based upon the electronic spin degree of freedom in such circuits. To this end, a spatially resolved, spin-polarized photocurrent mapping technique shall be applied to mesoscopic circuits defined in two-dimensional electron reservoirs of GaAs-based heterostructures. The spin-polarized photocurrents will be locally analyzed by an optoelectronic spin detector exploiting spin-split one-dimensional subbands of a quantum point contact (QPC). Hereby, mesoscopic spin-transport phenomena of a non-equilibrium spin population shall be explored in the ballistic and diffusive regime. Particular emphasize will be placed on spin scattering processes at the transition from a two-dimensional to a one-dimensional spin system. We furthermore expect insights into spin relaxation mechanisms induced by spin-orbit coupling terms, i.e. due to structural and bulk inversion asymmetry. The proposed experiments shall prepare ground for mesoscopic optoelectronic spin devices. Within the SPP, we further plan to transfer our confocal optoelectronic characterization scheme towards InAs-based and ZnO-based circuits in order to explore the spin-polarized photocurrent properties in these materials as well.

• DFG-Verfahren: Schwerpunktprogramme
• Teilprojekt zu: SPP 1285: Halbleiter-Spintronik