Analytical model for homogeneous upconversion in Er/sup 4+/-doped waveguides

Summary form only given. Interaction of two excited Er/sup 4+/ ions leads to the upconversion and nonlinear quenching of the /sup 4/I/sub 13/2/ level, which reduces pumping efficiency of Er-doped amplifiers and lasers. We propose an analytical model for description of the homogeneous upconversion in Er/sup 3+/-doped devices. The model is based on the modified continuous-time random-walk method applicable when quenching is strongly influenced by migration of excited ions (the hopping mechanism of quenching). Since migration in Er-doped media is typically much faster than the upconversion the assumption of the hopping mechanism is well justified.