Abstract

Stepowski has recently shown theoretically that diffracted stimulated emission should occur at certain angles when a medium is probed with intersecting dye laser beams capable of exciting a certain species in the medium. This was of great interest to us because it is wellknown that the stimulated emission rate can be considerably greater than the spontaneous emission rate in all cases where the radiational excitation rate exceeds the collisional quenching rate plus the spontaneous emission rate. Unfortunately, with a single laser beam, stimulated emission is difficult to detect because it occurs in the same direction and with the same phase and polarization as the exciting laser beam. By splitting the exciting laser beam into two equivalent beams that intersect at angle 2θ in the medium of interest and measuring the diffracted stimulated emission of an angle of 3θ (or 5θ, 7θ, etc.), it is possible to avoid the difficult (impossible) problem of separating the stimulated emission beam from the incident single laser beam.

Diffracted stimulated emission induced by two strong coherent crossed laser beams for concentration measurement

D. Stepowski
Appl. Opt. 18(23) 3967-3969 (1979)

Analytical evaluation of techniques for use of a laser Doppler velocimeter to measure flow and turbulence*

C. Y. She and L. S. Wall
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Breaking the diffraction resolution limit by stimulated emission: stimulated-emission-depletion fluorescence microscopy

Stefan W. Hell and Jan Wichmann
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Evaluating image resolution in stimulated emission depletion microscopy

Giorgio Tortarolo, Marco Castello, Alberto Diaspro, Sami Koho, and Giuseppe Vicidomini
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Evaluation of Mn⁵⁺-doped Sr₅(VO₄)₃F as a laser material based on excited-state absorption and stimulated-emission measurements

S. Kück, K. L. Schepler, and B. H. T. Chai
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