Structural properties of Pr3+ doped bismuth boro-tellurite glasses by Raman spectroscopy

Pr³⁺ doped bismuth borate glasses have some superior physical properties such as high thermal stability, low melting point, and good optical properties which are favorable for applications in a variety of optical devices. We used Raman spectroscopy to study the structural properties of 3 groups of bismuth glasses doped with Pr³⁺ ions: binary bismuth borate, bismuth boro-tellurite, and bismuth boro-tellurite containing CdSe nanoparticles. Glass samples with varying bismuth oxide content are prepared using the melt-quench technique. CdSe nanoparticles are grown in one of the bismuth boro-tellurite glasses by varying the annealing time. Raman spectra of glasses are obtained using a Nano Photon Raman spectrometer to analyze the structural properties. The Raman bands in the region 100 cm^-1 to 1600 cm^-1 have been identified, and assigned to their respective vibrational groups. The band at 138 - 387cm^-1, 412 - 748cm^-1 and 784 -1511cm^-1 are identified as vibrational modes of bismuth oxide, tellurium oxide and borate groups, respectively. Position and width of the Raman peaks clearly reflect changes in glass composition when the bismuth oxide content is varied.