Structural and thermal study of ZnTe nanocrystals doped with Cr and Mn in phosphate glasses

Abstract In this study, structural and thermal features of phosphate glasses doped with diluted magnetic semiconductors are investigated. The samples were ZnTe nanocrystals doped with different concentrations of Cr and Mn. UV-visible absorption spectra showed the presence of Cr2+ and Cr3+ ions into the matrix. Depolymerization of the phosphate network is observed by Raman spectroscopy due to the addition of Cr ions breaking the phosphate chains. The thermal diffusivity (D), thermal conductivity (K), specific heat capacity (ρc) and optical path variation with temperature (dS/dT) of samples are measured by thermal lens and ρc techniques. The thermal conductivity values show that although the formation of crystalline structures of ZnTe inside the matrix glasses leads to a decrease, the incorporation of the Cr and Mn do not show a definite trend. A monotonic reduction in optical path variation with temperature is observed with nanocrystal formation and Cr addition.