Optical and magneto-optical properties of neodymium and erbium doped gallium nitride epilayers

This work investigated the effects of applied magnetic fields on rare earth spectra and was able (using CEES) to determine Zeeman splittings and the associate effective g-values of the ions´ excited and ground states. The coupling of the Zeeman split transition strengths to the direction of the piezoelectric field present in GaN along the c-axis. This coupling between magnetic polarization and strain induced by defects or lattice mismatch may be related and essential to the strength of the remnant magnetization that is observed in ferromagnetic hysteresis loops and which show a dependence on defect levels, substrate, and growth conditions.