Infrared radiation properties of Ho3+ in multicomponent germanium tellurite glasses

摘要

Ho3+-doped and Ho3+/Yb3+-codoped multicomponent germanium tellurite (MGT) glasses with multifarious emission channels in the near-infrared wavelength region have been fabricated and characterized. Judd-Ofelt intensity parameters of Ho3+-doped MGT glasses are solved to be Omega(2) = 5.32 x 10(-20) cm(2), Omega(4) = 2.73 x 10(-20) cm(2), and Omega(6) = 1.12 x 10(-20) cm(2), indicating a higher asymmetric and stronger covalent environment around Ho3+ ions in MGT glasses. Efficient infrared fluorescences have been observed in MGT glasses, and spontaneous emission probabilities are derived to be 230.4, 79.9, and 138.3 s(-1) for the I-5(6) -> I-5(8), (F-5(4); S-5(2)) -> I-5(5), and I-5(7) -> I-5(8) radiative transitions, respectively. In Ho3+/Yb3+-codoped MGT glasses, the maximum stimulated emission cross-section of 2.0 mu m emission is calculated to be 4.93 x 10(-21) cm(2), and the corresponding gain cross-section is derived to be 3.62 x 10(-21) cm(2) when the excited state population fraction P reaches 0.8. Multifarious infrared emissions show that Ho3+ in MGT glasses is a good candidate for optical amplifiers and optoelectronic devices. (C) 2015 Optical Society of America