Temperature dependence of spectral-line intensities in YAG:Yb3+

On the basis of the detailed calculation of the matrix elements of the interaction of an optical electron of an impurity ion with lattice phonons taking into account the nonadibatic contributions, the Debye-Waller factors, homogeneous widths, and the shifts of no-phonon spectral lines of Yb 3+ ion in YAG are calculated. The temperature dependences of the intensities of the most intensive spectral lines are obtained. It is shown that with a decreasing temperature, the intensities of the spectral lines on the wavelengths 968.3 and 1030 nm are sharply increased.