Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Laser Spectroscopy Of Electronic Resonances: An Electro-Optic Technique For Probing Coherent And Incoherent Decay Processes

Ahmed H. Zewail

Published Dec 30, 1976• 4 citations

Abstract

A new technique is presented for measuring the incoherent resonance decay (IRD) and the coherent optical ringing of selectively (5 MHz) prepared electronic states. The method utilizes electro-optic switching of a single laser mode that is on or off resonance with respect to the homogeneous molecular packets in the excited ensemble. The technique was applied to a variety of systems (gases at low pressures, gases at relatively high pressures, and solids at low temperatures) to give information about their phase memory (optical T2 processes), radiative and radiationless decay (optical T1 processes), and to measure directly their optical transition moment between the ground state and the prepared electronic state. The theory of coherent and incoherent states is also given.

DOI: 10.1117/12.954871

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