Ferromagnetism above room temperature in bulk sintered gallium phosphide doped with manganese

Evidence for ferromagnetism in bulk sintered gallium phosphide (GaP) doped with 3% manganese, having a Curie temperature of 600 K considerably higher than previous observations, is obtained using ferromagnetic resonance (FMR) and AC magnetization measurements. The field position and line width of the resonance showed a strong temperature dependence characteristic of FMR spectra. A non-resonant derivative signal centered at zero field was also observed starting at 600 K further confirming high temperature ferromagnetism. AC magnetization measurements also show the existence of ferromagnetism at high temperature.