The nonradiative changeover costs follow the components WNR = W (0) exp(-alphap), wherever p is the number of phonons matching the energy hole. The nonradiative changeover rates of Er3+ exhibit temperature dependence according to the multiphonon relaxation theory. In Tm3+ the temperature dependence of nonradiative rest costs is difficult by https://erybyabcrystal72604.qodsblog.com/34836396/a-review-of-er-yb-yab-crystal