The electron-phonon coupling strength (g) has been calculated. The value of Ωλ parameters were calculated from the emission spectra using Judd-Ofelt theory. These parameters were used to predict radiative properties such as transition probabilities (AR), calculated branching ratios (βR) and stimulated emission cross-sections (σλ p ) for 5D0 →7FJ transitions. The results have shown that the 5D0 →7F2 transition of Eu3+ ions in BTe glass is very promising for laser emission and optical amplification. | Communications in Physics, Vol. 26, No. 1 (2016), pp. 25-31 DOI: OPTICAL PROPERTIES OF Eu3+ IONS IN BORO-TELLURITE GLASS NGO VAN TAM Nha Trang Institute of Reseach and Application of Technology, Nha Trang, Vietnam VU PHI TUYEN† Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam PHAN VAN DO Thuy Loi University, 175 Tay Son, Dong Da, Hanoi, Vietnam † E-mail: vptuyen@ Received 21 March 2016 Accepted for publication 11 April 2016 Abstract. Boro-tellurite (BTe) glass doped with concentrations of mol% of Sm3+ ions was prepared by melting method. Their excitation, emission spectra and lifetime have been investigated. Sideband phonon spectrum have recorded three peaks at 865, 1375 and 1763 cm−1 . The electron-phonon coupling strength (g) has been calculated. The value of Ωλ parameters were calculated from the emission spectra using Judd-Ofelt theory. These parameters were used to predict radiative properties such as transition probabilities (AR ), calculated branching ratios (βR ) and stimulated emission cross-sections (σλ p ) for 5 D0 →7 FJ transitions. The results have shown that the 5 D0 →7 F2 transition of Eu3+ ions in BTe glass is very promising for laser emission and optical amplification. Keywords: Boro-tellurite glass, Judd-Ofelt theory. Classification numbers: , . I. INTRODUTION The optical properties of trivalent rare-earth (RE3+ ) ions doped glasses have attracted the attention of scientists due to their wide applications in many optical devices like lasers, light converters, sensors, high-density memories and optical amplifiers [1–4]. The borate glasses offer excellent heat stability and lower melting temperature compared with other glasses but the pure borate based glasses possess high phonon energy in the order of 1300-1600 cm−1 [3, 4]. Tellurite oxide (TeO2 ) is a conditional glass former and forms glass only
