Electron paramagnetic resonance studies of Zn_1-xMn_xTe

Abstract

Electron paramagnetic resonance has been studied in Zn1-xMnxTe over a wide temperature range 20 K<or=T<or=290 K and a wide manganese concentration range 0.013<or=x<or=0.81. Our results show that, for lower manganese concentrations x<or=0.23, the EPR line can be represented by the Bloch model modified for broad resonance in the entire range of temperatures. For x>or=0.37 the resonance is detected at higher temperatures. The values of the relaxation time tau and the g-factor are obtained by fitting an expression for the EPR absorption line in the modified Bloch model to the experimental data. The high-temperature linewidth for x<or=0.37 is analysed within the exchange narrowing model. The calculated infinite-temperature linewidths are in good agreement with the extrapolated experimental values. It is found that the main contribution to the linewidth arises from the anisotropic superexchange.