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Updated: Oct 1, 2026

Measurement of Coherence Decay in GaMnAs Using Femtosecond Four-wave Mixing
Published on: December 3, 2013
Effect of optical spin injection on ferromagnetically coupled Mn spins in the III-V magnetic alloy semiconductor
A Oiwa1, Y Mitsumori, R Moriya
1Kanagawa Academy of Science and Technology, 3-2-1 Sakado, Takatsu-ku, Kawasaki 213-0012, Japan. oiwa@net.ksp.or.jp
Abstract:
We report on the new type of photoinduced magnetization in ferromagnetic (Ga,Mn)As thin films. Optically generated spin-polarized holes change the orientation of ferromagnetically coupled Mn spins and cause a large change in magnetization, being 15% of the saturation magnetization, without the application of a magnetic field. The memorization effect has also been found as a trace after the photoinduced magnetization. The observed results suggest that a small amount of nonequilibrium carrier spins can cause collective rotation of Mn spins presumably through the p-d exchange interaction.
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