Optical properties of trivalent terbium doped calcium fluorapatite

• Published in: Materials research bulletin Vol. 28; no. 6; pp. 605 - 613
• Main Authors: Tachihante, M., Zambon, D., Arbus, A., Zahir, M., Sadel, A., Cousseins, J.C.
• Format: Journal Article
• Language: English
• Published: London Elsevier Ltd 01.06.1993; Amsterdam Elsevier Science
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Photoluminescence; Physics; terbium; calcium; phosphates; fluorapatites; Calcium Fluophosphates; Temperature; Impurity density; Optical transition; Fluorescence; Cross relaxation; Experimental study; Inorganic compound; Luminescence decay; Sodium; Terbium; Radiationless transition; Codoping; Low temperature
• ISSN: 0025-5408; 1873-4227
• DOI: 10.1016/0025-5408(93)90057-K

The fluorescence of the Tb 3+ ion in the apatite Ca 10−2xNa xTb xF 2(PO 4) 6 (0 ≤ x ≤ 2) is reported. The active ion is quasi exclusively located in the C s site of the apatitic structure. Non radiative de-excitation from the 5D 3 level to the 5D 4 can be explained using cross-relaxation; the process is well described using the Inokuti and Hirayama model for a dipole-quadrupole interaction, leading to a Tb 3+ critical concentration of 2.9% and to a critical distance of 1.21 nm. Moreover, at room temperature, phonons play a role in the 5D 3 → 5D 4 relaxation, with a very weak probability.