Abstract

We demonstrate production of continuous coherent blue laser light by using a five-level system in rubidium vapor. Two low-power lasers, at 780 and $776\mathrm{nm}$, induce strong atomic coherence in the $5S–5P–5D$ states. The atoms decay to the $6P$ excited state, from which stimulated emission produces a coherent blue $\left(420\mathrm{nm}\right)$ beam. We have coupled both ground-state hyperfine levels, effecting coherence between four levels. The coherent blue output is enhanced by several mechanisms, including stronger coupling to a larger fraction of the atomic population, operation at a detuning such that the vapor is nominally transparent to the $780\mathrm{nm}$ pump field, reduced losses owing to optical pumping, and optimal phase matching. We report experimental findings and compare them with results from a semiclassical Maxwell–Bloch model.

© 2006 Optical Society of America

Collimated blue and infrared beams generated by two-photon excitation in Rb vapor

J. F. Sell, M. A. Gearba, B. D. DePaola, and R. J. Knize
Opt. Lett. 39(3) 528-531 (2014)

Intensity correlation in frequency upconversion via four-wave mixing in rubidium vapor

Yong Sup Ihn, Kwang-Kyoon Park, Yosep Kim, Young-Tak Chough, and Yoon-Ho Kim
J. Opt. Soc. Am. B 34(11) 2352-2357 (2017)

Efficient and stable single-photon counting at 1.55 μm by intracavity frequency upconversion

Haifeng Pan and Heping Zeng
Opt. Lett. 31(6) 793-795 (2006)

Experimental preparation of pure superposition states of atoms via elliptically polarized bichromatic radiation

Sergei A. Zibrov, V. L. Velichansky, A. S. Zibrov, A. V. Taichenachev, and V. I. Yudin
Opt. Lett. 31(13) 2060-2062 (2006)

Coherent 455 nm beam production in a cesium vapor

J. T. Schultz, S. Abend, D. Döring, J. E. Debs, P. A. Altin, J. D. White, N. P. Robins, and J. D. Close
Opt. Lett. 34(15) 2321-2323 (2009)