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Journal of Physics B Atomic Molecular and Optical Physics

Studies on coherent effects in double-resonance multiphoton ionization of sodium with pulsed lasers

Yun Shao, Dimitrios Charalambidis, Costas Fotakis

Published Nov 28, 1996• 2 citations
Publisher

Abstract

An experimental study of doubly resonant multiphoton ionization of Na has been carried out. Coherence effects, such as AC - Stark splitting and population trapping, have been manifested in different coupling schemes, i.e. ladder, lambda, vee configurations. These effects have been investigated in terms of their dependence on the laser intensity and resonance detuning, as well as the state of the laser polarization. The experimental results are qualitatively interpreted in terms of a few level system.

DOI
10.1088/0953-4075/29/22/015

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We present experimental results in AC-Stark splitting of an autoionizing state probed by a multiphoton process. In the experiment performed in calcium, the 3d4f 1 P 1 autoionizing state is single-photon coupled with the 4s6s 1 S 0 excited state. The splitting caused by this coupling is probed by three-photon excitation from the ground state. Detuning and laser intensity dependent measurements have been carried out in a collision-free environment. The experimental results can be interpreted and modelled in terms of a few levels system.