OPTICAL CHARACTERIZATION OF INTER-STARK ENERGY-LEVELS AND EFFECTS OF TEMPERATURE ON SHARP EMISSION-LINES OF ND3+ IN CAZN(2)Y(2)GE(3)O12

A characterization of the Stark components of the I-4(9/2) and I-4(11/ 2) manifolds have been performed using the room temperature fluorescen ce spectra for the F-4(3/2) --> I-4(9/2) and F-4(3/2) -->I-4( )11/2 tr ansitions of Nd3+ in CaZn2Y2Ge3O12 laser crystal. The temperature depe ndencies of the linewidths, positions, and line shifts of the inter-St ark transitions of the 939.4 (R-1 --> X-5) and 1058.8 (R-1 --> Y-1) nm lines within the respective intermanifold transitions of F-4(3/2) --> I-4(9/2) and F-4(3/2) --> I-4(11/2) have been also investigated. The linewidths of these transitions were found to increase with increasing temperature. The 939.4 nm Line shifted toward the shorter wavelength, while the 1058.8 nm line shifted toward the longer wavelength. The ex perimental results of the temperature-dependent widths and shifts of t hese emission Lines are explained using the phonon-ion interaction the ory which assumes the Debye model for phonons in crystalline solids. ( C) 1998 Elsevier Science B.V. All rights reserved.