Optically Induced Magnetization in a Dilute Magnetic Semiconductor:Hg1−xMnxTe

This paper reports the observation of light-induced magnetization in ${\mathrm{Hg}}_{1-x}{\mathrm{Mn}}_x\mathrm{Te}$ by a novel technique combining optical pumping and superconducting quantum interference detection. We show that the magnetization is due to orientation of Mn ions caused by spin transfer from polarized electrons and holes to Mn centers in the process of spin-flip exchange scattering. This interpretation goes beyond a mean-field approach. The effect furnishes direct information on the spin-lattice relaxation in dilute magnetic semiconductors.