Increase in the efficiency of spin detection based on GaAsSb by applying a longitudinal magnetic field or a postgrowth annealing process

摘要

A substantial improvement in the efficiency of spin detection based on GaAs_(0.94)Sb_(0.06) is realized by applying either a longitudinal magnetic field or a postgrowth annealing process. The degree of optical spin polarization can be increased from ～19 to ～40% at ～105K under a longitudinal magnetic field of 10T. On the other hand, through the shortening of the electron lifetime by the use of a postgrowth annealing process, the efficiency for optical spin detection can be enhanced by a factor of nearly 4 from ～6 to ～23% at ～180K under zero external magnetic field.