Yellow and blue emission from BaO-(ZnO/ZnF2)-B2O3-TeO2 glasses doped with Dy3+ for laser medium and scintillation material applications

Barium zinc oxide and barium zinc oxyfluoride borotellurite glass doped with Dy3+ have been comparatively investigated on physical, structural, optical and luminescence properties. Both glasses were prepared by melt and quenching technique. The FTIR spectra show weaker vibration of OH group in Dy3+ doped oxyfluoride glass than oxide glass due to fluoride existence. It results to stronger 4f-4f transition of oxyfluoride than oxide glass. The highest absorption band centered at 1269 nm of both glasses corresponds to E-6(15/2) -> F-6(11/2) transition of Dy3+. The prepared glasses were excited by photon with 388 nm and emitted white light due to the integration of strong yellow 575 nm (F-4(9/2) -> H-6(13/2)) and blue 482 nm (F-4(9/2) -> H-6(15/2)) emission. X-ray luminescence also were affeted from less vibration of OH group in oxyfluoride glass and showed similar strong emission pattern to the photoluminescence spectra. The calculations of radiative properties were done by Judd-Ofelt theory. The oxyfluoride glass showed more asymmetry of Dy3+ environment with higher J-O parameter (Omega(2)) value than oxide glass. The radiative transition probability (A(R)), stimulated emission cross-sections (sigma) and branching ratios (beta(R)) of oxyfluoride glass were higher than oxide glass which perform lower laser threshold and higher gain laser application. Both glasses in this work performed the high potential for photonic applications, but addition of fluoride made barium zinc oxyfluoride borotellurite glass more suitable than barium zinc oxide borotellurite glass for usage as a scintillation, laser medium and other white-light photonic material.