The excitonic spin relaxation process in cubic GaN is observed by spin-dependent pump and probe reflectance measurements with subpicosecond time resolution. The spin polarization presents at temperatures lower than 100 K. The spin relaxation times at 15-75 K are found to be longer than 5 ns and short spin relaxation times on the picosecond order are not present. Although these long spin relaxation times are in striking contrast to the subpicosecond spin relaxation of A -band free excitons in hexagonal GaN, they are consistent with the dependence that spin relaxation time becomes longer for wider-band gap zinc blende semiconductors.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)