Collimated Blue and Infrared Beams Generated by Two-Photon Excitation in Rb Vapor

Authors

J. F. Sell, U.S. Air Force AcademyFollow
M. A. Gearba, University of Southern MississippiFollow
B. D. DePaola, Kansas State University
R. J. Knize, U.S. Air Force Academy

Document Type

Article

Publication Date

2-1-2014

Department

Physics and Astronomy

School

Mathematics and Natural Sciences

Abstract

Utilizing two-photon excitation in hot Rb vapor we demonstrate the generation of collimated optical fields at 420 and 1324 nm. Input laser beams at 780 and 776 nm enter a heated Rb vapor cell collinear and circularly polarized, driving Rb atoms to the 5D_5/2 state. Under phase-matching conditions coherence among the 5S_1/2 → 5P_3/2 → 5D_5/2 → 6P_3/2 transitions produces a blue (420 nm) beam by four-wave mixing. We also observe a forward and backward propagating IR (1324 nm) beam, due to cascading decays through the 6S_1/2 → 5P_1/2 states. Power saturation of the generated beams is investigated by scaling the input powers to greater than 200 mW, resulting in a coherent blue beam of 9.1 mWpower, almost an order of magnitude larger than previously achieved. We measure the dependences of both beams in relation to the Rb density, the frequency detuning between Rb ground-state hyperfine levels, and the input laser intensities. (C) 2014 Optical Society of America

Publication Title

Optics Letters

Volume

39

Issue

3

First Page

528

Last Page

531

Recommended Citation

Sell, J., Gearba, M., DePaola, B., Knize, R. (2014). Collimated Blue and Infrared Beams Generated by Two-Photon Excitation in Rb Vapor. Optics Letters, 39(3), 528-531.
Available at: https://aquila.usm.edu/fac_pubs/8041