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 quasi-molecular interaction promotes rapid energy transfer between the 4p ¹P₁ level and the 4p ³P_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.

© 1991 Optical Society of America

422.7-nm atomic filter with superior solar background rejection

Jerry A. Gelbwachs
Opt. Lett. 15(4) 236-238 (1990)

Proposed Fraunhofer-wavelength atomic filter at 534.9 nm

Jerry A. Gelbwachs
Opt. Lett. 15(20) 1165-1167 (1990)

Experimental demonstration of internal wavelength conversion in the magnesium atomic filter

Y. C. Chan, M. D. Tabat, and J. A. Gelbwachs
Opt. Lett. 14(14) 722-724 (1989)

Lamp-pumped thallium atomic line filter at 535.046 nm

Bernhard P. Oehry, Walter Schupita, and Gottfried Magerl
Opt. Lett. 16(20) 1620-1622 (1991)

Solar background rejection by a pressure-broadened atomic resonance filter operating at a Fraunhofer wavelength

J. A. Gelbwachs and M. D. Tabat
Opt. Lett. 14(4) 211-213 (1989)