We discuss our approach to realizing all-electrical spin injection and detection in GaAs via ferromagnetic metals and oxide tunnel barriers. A critical requirement is suppression of the formed Schottky barrier, which causes conductivity mismatching and prevents detection in reverse bias. However, initial I-V measurements of engineered GaAs/AlOx/CoFe tunnel contacts still show too high resistance area products in comparison to the semiconductor conductance, due to a large Schottky barrier contribution. To this end, optimized doping levels of the tunnel contacts and semiconductor spin transport region are calculated. Secondly, control over the magnetic properties of injector and detector electrode is established by designing both electrodes to have different switching fields, due to different widths.
|Title of host publication||Proceedings of the 4th international conference on physics and applications of spin related phenomena in semiconductors (PASPS-IV), 15-18 august 2006, Sendai, Japan|
|Place of Publication||Sendai, Japan|
|Publication status||Published - 2006|
|Event||4th International Conference on Physics and Applications of Spin Related Phenomena in Semiconductors (PASPS-IV), August 15-18, 2006, Sendai, Japan - Sendai, Japan|
Duration: 15 Aug 2006 → 18 Aug 2006
|Conference||4th International Conference on Physics and Applications of Spin Related Phenomena in Semiconductors (PASPS-IV), August 15-18, 2006, Sendai, Japan|
|Period||15/08/06 → 18/08/06|