The optical absorption study of cadmium-zinc phosphate glasses

摘要

The study of optical absorption spectra provides a very useful tool for the investigation of optically induced transitions and an insight into the energy gap and band structure of crystalline and non-crystalline materials. Experimental results on optical absorption in glassy materials have been reported by various workers 1-3. The measurements of optical absorption coefficients have generally shown an exponential dependence on photon energy 4. However, the presence of tails in the absorption has also been reported in phosphate glasses 5. These tails are assumed to be due to the presence of impurities, structural defects or other types of inhomogeneities that may be present in these glasses 6. The variation of optical band gap of phosphate glasses has been studied as a function of composition 7,8 and applied electric field 6, 9,10.