Spin coherence and dephasing in GaN - art. no. 121202

Time-resolved Faraday rotation is used to measure electron spin coherence i n n-type GaN epilayers. Despite densities of charged threading dislocations of similar to5 x 10(8) cm(-2), this coherence yields spin lifetimes of sim ilar to 20 ns at T=5 K, and persists to room temperature. Spin dephasing is investigated in the vicinity of the metal-insulator transition. The depend ence on both magnetic field and temperature is found to be qualitatively si milar to previous studies in n-type GaAs, suggesting a common origin for sp in relaxation in these systems.