Nonradiative energy transfer from Cr3+ to Nd3+ ions in glasses with high neodymium concentrations

An investigation is made of the possibility of improving the optical pumping efficiency of laser phosphate glasses with high neodymium concentrations by introducing Cr³+ ions as Nd³⁺ luminescence sensitizers. The results indicate efficient nonradiative excitation energy transfer from Cr³⁺ to Nd³⁺ ions in glasses with high concentrations at temperatures of 77°K and 300°K with transfer probabilities higher than 10⁵ and 10⁶ sec^–1, respectively. The Cr³⁺–Nd³⁺ interaction process is more efficient than the intracenter nonradiative losses in Cr³⁺. This is promoted by the proximity of the interacting Nd³⁺ and Cr³⁺ ions and the large overlap of the optical spectra of the energy donors and acceptors.