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

A substantial improvement in the efficiency of spin detection based on GaAs0.94Sb0.06 is realized by applying either a longitudinal magnetic field or a postgrowth annealing process. The degree of optical spin polarization can be increased from similar to 19 to similar to 40% at similar to 105K under a longitudinal magnetic field of 10 T. 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 similar to 6 to similar to 23% at similar to 180K under zero external magnetic field. (C) 2016 The Japan Society of Applied Physics