Electron spin resonance in Ge nanowires doped with Mn

Abstract Electron spin resonance (ESR) is measured in arrays of Ge nanowires (NWs) doped with Mn, x =1% and 3%. Contributions due to localized magnetic ions and charge carriers to the magnetic properties of NWs are observed. Doping with Mn causes a ferromagnetic ordering at temperatures up to 285 K. Zero-field ferromagnetic resonance (FMR) is observed in Ge 0.97 Mn 0.03 NWs at room temperature. We demonstrate the influence of the Mn concentration on the angular dependence and linewidth of the FMR spectra. We found a remarkable correlation between parameters of the FMR on Mn ions and the paramagnetic resonance on spin-polarized carriers.