SPECTRAL PROPERTIES OF ND3+-DOPED RO-CENTER-DOT-NA2O-CENTER-DOT-AL2O3-CENTER-DOT-P2O5 (R=MG, CA, BA) GLASS SYSTEM

The dependence of spectral properties of the Nd3+-doped (45-x)RO.xNa(2)O.2.5Al(2)O(3).52.5P(2)O(5) (R=Mg, Ca, Ba, 0 less than or equal to x less than or equal to 31, mol%) glasses on RO and on its substitution with Na2O was investigated. Absorption, fluorescence spectra and lifetimes were measured. Both the stimulated emission cross section and the spontaneous emission probability for the F-4(3/2)-->I-4(11/2) transition of Nd3+ in glass were calculated. The results indicate that the effect of RO depends on its ionic field strength and that the substitution of RO with Na2O loosens the glass structure so as to lower the degree of disorder of the phosphate chain structure. A stimulated emission cross section as large as 4.2 x 10(-20) cm(2) and half-lifetime concentration as high as 8 x 10(20) ions/cm(3) were obtained.