Exchange broadening of EPR line in ZnO:Co
نویسندگان
چکیده
We study the X -band EPR spectra of Co in single crystalline Zn1 xCoxO (x = 0.001–0.075) thin films grown by plasma-assisted molecular beam epitaxy. By analyzing the EPR linewidth behavior we argue that the exchange-narrowing model, usually applied to Mn-based II-VI DMS, fails here and that a combined effect of exchange and dipolar broadening can explain the linewidth variation with Co content and temperature.
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