Broadband electrical detection of spin excitations in (Ga,Mn)As using a   photovoltage technique
  We report on microwave photovoltage and simultaneous magnetotransport measurements in a (Ga,Mn)As film oriented normal to the magnetic field. We detect the ferromagnetic resonance over a broad frequency range of 2 GHz to 18.5 GHz and determine the spectroscopic g-factor and separate the Gilbert from the inhomogeneous contribution to magnetization relaxation. Temperature dependent measurements below the saturation magnetization indicate that the photovoltage signal can serve as a sensitive tool to study the crystal anisotropy. We demonstrate that the combination of spin dynamics with charge transport is a promising tool to study microstructured ferromagnetic semiconductor samples. 
Andr\'e Wirthmann, Xiong Hui, N. Mecking, Y. S. Gui, T. Chakraborty,   M. Reinwald, C. Sch\"uller, W. Wegscheider, C.-M. Hu