TEMPERATURE DEPENDENCIES OF LINEWIDTHS, POSITIONS, AND LINE SHIFTS OFSPECTRAL TRANSITIONS OF TRIVALENT NEODYMIUM IONS IN BARIUM MAGNESIUM YTTRIUM GERMANATE LASER HOST

The spectral widths, positions, and shifts of the sharp emission Lines for the R-1-->X-5 and R-2-->Y-3 inter-Stark transitions within the re spective intermanifold transitions of F-4(3/2)-->I-4(9/2) and F-4(3/2) -->I-4(11/2) of Nd3+ ions in Ba0.25Mg2.75Y2Ge3O12 laser host have been investigated as a function of temperature. The linewidths of these tr ansitions increased as the temperature of the host crystal was increas ed. The emission line for the R-1-->X-5 transition shifted toward the shorter wavelength (blue shift), while the emission line for the R-2-- >Y-3 transition shifted toward the longer wavelength (red shift) with increasing temperature. The experimental results of the temperature-de pendent linewidths and line shifts of these transitions are explained in light of the existing theory of the phonon-ion interaction in cryst alline solids. (C) 1998 American Institute of Physics. [S0021-8979(98) 08203-6].