Abstract

Frequency stabilization of CW lasers to high-finesse, narrow linewidth Fabrv-Perot (FP) cavities is an attractive way for performing very high sensitivity spectroscopy. When a weak absorber is placed between the mirrors of a FP cavity with a length d and finesse F, the effective absorption length is ≈2dF/π. With high reflectivity mirrors it is possible to achieve absorption lengths of tens of km in a table-top setup.

© 1998 IEEE