Energy transfer in Yb3+-Er3+-codoped bismuth borate glasses

The mechanism of energy transfer from Yb3+ to Er3+ ions has been studied in bismuth borate glasses with a serial Yb3+ concentration. The analysis of the donor fluorescence decay with a low concentration has been used to determine the multipole character of the energy transfer. The energy-transfer microparameters were determined and used to calculate the migration-assisted energy-transfer rates on the basis of the hopping model, which are in agreement with those obtained by fitting the fluorescence decay curves. An efficient energy transfer from Yb3+ : F-2(5/2) to Er3+ : I-4(11/2) in the bismuth borate glasses has been demonstrated. (C) 2007 Optical Society of America.