The optical properties of Cr3+ ions in the disordered LaSr2Ga11O20 crystal have been investigated through absorption, emission, excitation spectra. Polarized excitation measurements allows us to evaluate the crystal field parameters and to infer the distortion of the octahedral site of Cr3+. In spite of the relatively low value of the crystal field (Dq/B = 2.26) obtained from optical data, the emission spectra are constituted by two narrow lines. This behavior, typical of strong field material, is explained by an even lower value of the crystal field corresponding to the 2E, 4T2 crossing point obtained by means of the Tanabe-Sugano diagram. The value of the splitting and the width of the emission lines, intermediate between crystals and glasses, confirm the disordered structure of this crystal.
Luci, A., Casalboni, M., Castrignano, T., Grassano, U.m., Kaminskii, A. (1995). Optical properties of Cr3+-ions in LaSr2Ga11O20. RADIATION EFFECTS AND DEFECTS IN SOLIDS, 135(1 -4 pt 2), 227-230.
Optical properties of Cr3+-ions in LaSr2Ga11O20
CASALBONI, MAURO;GRASSANO, UMBERTO MARIA;
1995-01-01
Abstract
The optical properties of Cr3+ ions in the disordered LaSr2Ga11O20 crystal have been investigated through absorption, emission, excitation spectra. Polarized excitation measurements allows us to evaluate the crystal field parameters and to infer the distortion of the octahedral site of Cr3+. In spite of the relatively low value of the crystal field (Dq/B = 2.26) obtained from optical data, the emission spectra are constituted by two narrow lines. This behavior, typical of strong field material, is explained by an even lower value of the crystal field corresponding to the 2E, 4T2 crossing point obtained by means of the Tanabe-Sugano diagram. The value of the splitting and the width of the emission lines, intermediate between crystals and glasses, confirm the disordered structure of this crystal.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
