Journal of Physics B Atomic Molecular and Optical Physics

Control of the emission channels energy flow in a nonlinear laser–potassium atom interaction

Dionysios Pentaris, Thomas Efthimiopoulos, Nikolaos Merlemis, A. Lyras

Published Sep 21, 2012• 3 citations

Abstract

A numerical study of the emissions of a four-level potassium atom excited either by a single pulse or by a pair of temporally separated pulses is presented. For a low-intensity single-pulse two-photon excitation (|4S1/2〉↔|6S1/2〉), parametric emissions along path-1 (|6S1/2〉↔|5P3/2〉↔|4S1/2〉) are generated while along path-2 (|6S1/2〉↔|4P3/2〉↔|4S1/2〉) are essentially inactive. But for high single-pulse excitation, the path-1 emissions saturate and delayed path-2 amplified spontaneous emissions appear. It is shown that in the case of a double-pulse excitation scheme, proper temporal separation of the pulses and saturation of path-1 emissions caused by the first pulse can be applied to selectively transfer the excitation energy from path-1 to path-2 emissions.

DOI: 10.1088/0953-4075/45/20/205505

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