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arXiv · 0806.0785

Broadband electrical detection of spin excitations in (Ga,Mn)As using a photovoltage technique

André Wirthmann·Xiong Hui·N. Mecking·Y. S. Gui·T. Chakraborty·M. Reinwald·C. Schüller·W. Wegscheider·C. -M. Hu
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Abstract

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.

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André Wirthmann, Xiong Hui, N. Mecking, Y. S. Gui, T. Chakraborty, M. Reinwald, C. Schüller, W. Wegscheider, C. -M. Hu. 2008-06-04. Broadband electrical detection of spin excitations in (Ga,Mn)As using a photovoltage technique. https://doi.org/10.1063/1.2943280

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