A 20-fold increase over the single path optical absorption is demonstrated with a low loss medium placed in a resonant cavity. This has been applied to laser cooling of Yb:ZBLAN glass resulting in 90% absorption of the incident pump light. A coupled-cavity scheme to achieve active optical impedance matching is analyzed.
@article{arxiv.0909.3136,
title = {Cavity-enhanced absorption for optical refrigeration},
author = {Denis V. Seletskiy and Michael P. Hasselbeck and Mansoor Sheik-Bahae},
journal= {arXiv preprint arXiv:0909.3136},
year = {2011}
}