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arXiv · 0906.0785

Current-Induced Spin Polarization in Gallium Nitride

W. F. Koehl·M. H. Wong·C. Poblenz·B. Swenson·U. K. Mishra·J. S. Speck·D. D. Awschalom
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Abstract

Electrically generated spin polarization is probed directly in bulk GaN using Kerr rotation spectroscopy. A series of n-type GaN epilayers are grown in the wurtzite phase both by molecular beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD) with a variety of doping densities chosen to broadly modulate the transverse spin lifetime, T2*. The spin polarization is characterized as a function of electrical excitation energy over a range of temperatures. Despite weak spin-orbit interactions in GaN, a current-induced spin polarization (CISP) is observed in the material at temperatures of up to 200 K.

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W. F. Koehl, M. H. Wong, C. Poblenz, B. Swenson, U. K. Mishra, J. S. Speck, D. D. Awschalom. 2009-06-03. Current-Induced Spin Polarization in Gallium Nitride. https://doi.org/10.1063/1.3194781

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