Nicolas M. Khaidukov

Photoluminescence of Eu3+ in KYF4 and KLuF4

Abstract Using selective dye-laser excitation between 17250 and 17350 cm−1, the Stokes and anti-Stokes emission spectra arising from four Eu3+ centres have been isolated in KYF4 and KLuF4.Our results show that the Eu3+ ions occupy only four sites in KYF4, whereas the structural study foresees six sites. The Eu3+ sites of KLuF4 are very similar to those of KYF4.

Optical excitation of Nd3+ pairs in CsGd2F7 crystals

CsGd 2 F 7 :N d3‘ crystals have been studied by laser selective excitation and time-resolved spectroscopy. These studies have been made at low temperatures with crystals containing 0.3}3 at% of Nd3‘ ion substituting for Gd3‘ ions. Energy levels and dynamic characteristics of infrared and ultraviolet (up-converted) luminescence, associated with some Nd3‘ pairs, were determined. Internal ion de-excitation and energy transfer processes between Nd3‘ ions in pairs or in clusters are discussed here. ( 1999 Elsevier Science B.V. All rights reserved. PACS: 78.55; 78.50; 78.40.E