Berlin 2015 – scientific programme

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

HL: Fachverband Halbleiterphysik

HL 70: Spintronics: Mobile electrons and holes (with MA/TT)

HL 70.3: Talk

Thursday, March 19, 2015, 10:30–10:45, ER 164

Spin injection through Fe/GaAs Schottky contacts — •Lennart-Knud Liefeith, Rajkiran Tholapi, Max Hänze, Ann-Kathrin Michel, Taras Slobodskyy, and Wolfgang Hansen — Institut für Festkörper- und Nanostrukturphysik, Hamburg, Hamburg

The understanding of the dominant mechanism of spin injection through the Fe/GaAs interface is crucial for spintronics applications. It was suggested that the spin injection process is controlled by thermal activation of surface states at the ferromagnet/semiconductor interface [1]. To test this theory we investigated the bias dependence of the spin injection efficiency as well as the electrical properties of the interface. The measurements were carried out using non-local spin detection devices at liquid helium temperatures and backed up by magneto optical Kerr effect and magnetic force microscopy measurements on the electrodes. We found that the post growth annealing strongly influences the spin injection efficiency and a notable asymmetry of the spin injection efficiency depending on the applied bias was observed.
[1] Q. U. Hu et. al., Spin accumulation near Fe/GaAs(001) interfaces: The role of semiconductor band structure, Physical Review B 84, 085306 (2011)