Blue luminescence in YVO4 and KGd(WO4)2 crystals excited by CW 1064-nm radiation
Abstract
Upconversion luminescence near λ = 475 nm is studied in KGd(WO4)2 and YVO4 crystals excited by cw radiation at a wavelength of 1064 nm. The luminescence spectra for intracavity and extracavity excitation are compared. The upconversion emission of a YVO4 crystal excited outside the cavity is studied in detail. The spectrum recorded in the visible and near-IR regions exhibits luminescence bands around 475, 650, and 800 nm, which coincide with the 1 G 4 → 3 H 6 and 1 G 4 → 3 F 4 transitions, as well as with the 1 G 4 → 3 H 5 and 3 H 4 → 3 H 6 transitions of Tm3+ ions. Blue upconversion slope n was measured to be 1.3-1.6, which is considerably lower than that for the three-photon excitation process. The reasons for the anomalous value of n are discussed.
- Publication:
-
Optics and Spectroscopy
- Pub Date:
- November 2015
- DOI:
- 10.1134/S0030400X15110144
- Bibcode:
- 2015OptSp.119..759K