Optical-absorption intensities of neodymium-doped lead molybdate

Abstract

Relative intensities of absorption bands of PbMo${\mathrm{O}}_4$:${\mathrm{Nd}}^{3+}$ have been measured at 300 and 550°K and at liquid-He temperatures. The Judd-Ofelt theory has been applied to interpret these intensities. In the high-temperature limit, the theory is able to explain the observed data reasonably well. At liquid-He temperature the observed and calculated intensities show poor agreement when the site symmetry of the Nd ion is approximated to $D_{2d}$. However, the agreement improves considerably with the use of the actual site symmetry $S_4$. Some possible reasons for the discrepancies which still remain are discussed.