Hole-burning spectroscopy of thulium chelates

The spectral hole-burning properties of four Tm3+ chelates, specifically beta-diketone tris chelates of thulium blended in a poly (methyl methacrylate) matrix are presented. Persistent spectral hole burning was observed at the H-3(4)(1) <-- H-3(6)(1) transition of the Tm3+ ion near 795 nm in all of the materials. The holewidth was found to be in the range 180-360 MHz and the hole lifetime is longer than 10 h at 1.4 K. A complex hole profile which was best described by the superposition of two Lorentzians was observed. Temperature cycling experiments were performed. The maximum annealing temperature was determined for all complexes, and its correlation with the size of the side groups was established. The aim of our research was to characterize these novel materials, as well as to evaluate their prospective for optical hole-burning frequency- and time-domain storage applications. (C) 2000 Elsevier Science B.V. All rights reserved.