Photoluminescence from ZnS1ÀxTex alloys under hydrostatic pressure
نویسندگان
چکیده
ZnS12xTex (0.022) isoelectronic centers. The pressure coefficients of the emission bands are smaller than those of alloy band gaps from 48% to 7%. The difference of the pressure coefficient of the emission band and the band gap increases when the binding energy of Ten centers decreases. It seems contrary to our expectation and needs further analysis. The integrated intensities of emission bands decrease with increasing pressure due to the decreasing of the absorption coefficient associated with the Ten centers under pressure. According to this model the Stokes shifts between the emission and absorption bands of the Ten centers are calculated, which decrease with the increasing Te composition in alloys.
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