Internal magnetic fields in thin ZnSe epilayers

TL;DR

This study investigates strain-induced spin-splitting in thin ZnSe epilayers, revealing how it varies with external conditions and crystal orientation using advanced spectroscopic and structural characterization techniques.

Contribution

It provides a detailed analysis of how strain and external parameters influence spin-splitting in ZnSe epilayers, combining spectroscopic and structural measurements for comprehensive understanding.

Findings

Spin-splitting increases with applied voltage and temperature.

Spin-splitting is highly dependent on crystal direction.

Strain effects are quantified using photoluminescence and x-ray diffraction.

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].