Yang G F, Zhang Q Y, Li T, Shi D M, Jiang Z H
Institute of Optical Communication Materials, South China University of Technology, Guangzhou 510641, People's Republic of China.
Spectrochim Acta A Mol Biomol Spectrosc. 2008 Jan;69(1):41-8. doi: 10.1016/j.saa.2007.03.006. Epub 2007 Mar 15.
We investigate the spectroscopic properties of the 1.5-microm emission from the (4)I(13/2)-->(4)I(15/2) transition of Er(3+) ions in bismuth-germanate-lead glasses for applications in broadband fiber amplifiers. The emission peak locates at 1532nm with a full width at half-maximum (FWHM) of approximately 65nm. The measured lifetime and the calculated emission cross-section of this transition are 3.3ms and 8.66x10(-21)cm(2), respectively. IR-to-green-upconversion occurs simultaneously upon excitation of the 1.5-microm emission with a commercially available 980nm laser diode. Effects of PbF(2) content on the thermal stability, structure and spectroscopic properties of Er(3+)-doped bismuth-germanate-lead glasses have been examined. We find that the substitution with PbF(2) provides a couple of potentials: shortening the UV cutoff band and decreasing the phonon energy of host glasses. Codoping of Yb(3+) significantly enhances both the green-upconversion and 1.5-microm emission intensity by means of a nonradiative Yb(3+)-->Er(3+) energy transfer. Energy transfer processes and nonradiative phonon-assisted decays could account for the population of the (2)H(11/2) level, which is an emitting level of the green-upconversion of Er(3+). The results indicate the possibility towards the development of bismuth-germanate-lead based glasses as photonics devices.
我们研究了锗酸铋铅玻璃中铒离子（Er(3+)）从（4）I(13/2)跃迁到（4）I(15/2)产生的1.5微米发射的光谱特性，用于宽带光纤放大器。发射峰位于1532纳米处，半高宽（FWHM）约为65纳米。该跃迁的测量寿命和计算得到的发射截面分别为3.3毫秒和8.66×10(-21)平方厘米。使用市售980纳米激光二极管激发1.5微米发射时，会同时发生红外到绿光的上转换。研究了PbF(2)含量对掺铒锗酸铋铅玻璃的热稳定性、结构和光谱特性的影响。我们发现用PbF(2)替代有几个潜在作用：缩短紫外截止带并降低基质玻璃的声子能量。共掺杂镱离子（Yb(3+)）通过非辐射的Yb(3+)→Er(3+)能量转移显著增强了绿光上转换和1.5微米发射强度。能量转移过程和非辐射声子辅助衰变可以解释（2）H(11/2)能级的粒子数，该能级是Er(3+)绿光上转换的发射能级。结果表明了开发基于锗酸铋铅的玻璃作为光子器件的可能性。
