Fluorescence and absorption spectra of rare earth metaphosphate glasses

The rare earth elements (R) form a series of highly stable glasses with com positions in the vicinity of (R2O3)(0.25)(P2O5)(0.75) which include the mos t magnetic oxide glasses yet found and in consequence show a wide variety o f fundamentally interesting and useful magneto-optical properties. To provi de detailed comparative information of the optical properties of the series of rare earth doped metaphosphate glasses needed for device applications t he absorption and fluorescence spectra of glasses modified with Pr Nd, Sm, Eu, Tb, Dy, Ho and Er have been determined over the wavelength range 400-17 50 nm. By comparing the measured transition wavelengths with those found in the optical spectra known for other hosts of rare earth ions, it is possib le to account for virtually all the observed optical features. To understan d further the magnetic and magneto-optic properties of these glasses, it is necessary to extend knowledge of the valence states of rare earth ions in this type of host. The optical spectra show that the 4f transitions assigne d to the peaks correspond to the trivalent state alone for all of the ions.