Optics Letters

Passive Fraunhofer-wavelength atomic filter at 4227 nm

Jerry A. Gelbwachs, Yat C. Chan

Published Mar 1, 1991• 13 citations

Abstract

We have demonstrated 25% internal photon conversion efficiency of a new passive atomic filter. The signal wavelength matches an intense Fraunhofer line at 422.7 nm, thereby offering enhanced sunlight rejection. A quasimolecular interaction promotes rapid energy transfer between the 4p (1)P(1) level and the 4p (3)P(J) level of neutral calcium for wavelength shifting of 422.7-nm light into 657.3-nm emission. We discuss augmentation of the photon conversion efficiency by radiation trapping.

DOI: 10.1364/ol.16.000336

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