Abstract

Recently, there is a renewed interest in obtaining short wavelength solid state lasers through upconversion schemes. Yb sensitized upconversion energy transfer is specially attractive for this purpose because of the ability of high power InGaAs diode lasers to pump Yb. Yb, Ho upconversion energy transfer is relatively simple compared to upconversion involving other rare earth ions. Although a Yb sensitized Ho green laser has been realized at 77 K in BaY₂F₈ [1], no such lasing has been achieved at room temperature. In searching for a more suitable host for the room temperature Yb, Ho green upconversion laser we have carried out a systematic spectroscopic study on the Yb, Ho upconversion processes in BaY₂F₈ (BYF), KYF₄ (KYF), and LiYF₄ (YLF). Based on the detailed absorption, emission and fluorescence decay data, KYF is shown to be a promising host.

© 1993 Optical Society of America