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Internal magnetic fields in thin ZnSe epilayers

S. Ghosh·N. P. Stern·B. Maertz·D. D. Awschalom·G. Xiang·M. Zhu·N. Samarth
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Abstract

Strain induced spin-splitting is observed and characterized using pump-probe Kerr rotation spectroscopy in n-ZnSe epilayers grown on GaAs substrates. The spin-splitting energies are mapped out as a function of pump-probe separation, applied voltage, and temperature in a series of samples of varying epilayer thicknesses and compressive strain arising from epilayer-substrate lattice mismatch. The strain is independently quantified using photoluminescence and x-ray diffraction measurements. We observe that the magnitude of the spin splitting increases with applied voltage and temperature, and is highly crystal direction dependent, vanishing along [1 1-bar 0].

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S. Ghosh, N. P. Stern, B. Maertz, D. D. Awschalom, G. Xiang, M. Zhu, N. Samarth. 2006-09-24. Internal magnetic fields in thin ZnSe epilayers. https://doi.org/10.1063/1.2404600

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