FREE INDUCTION DECAY FROM CARBONYL SULFIDE IN THE THZ SPECTRAL RANGE
Loading...
Date
2006
Journal Title
Journal ISSN
Volume Title
Publisher
Ohio State University
Abstract
A typical pump-probe pulsed THz set-up have been used for Time Domain Spectroscopy experiment in order to investigate free induction decay in carbonyle sulfide (COS).}, \underline{\textbf{77}, (2076),1997}} In the detected time domain signal, a transmitted pulse followed by commensurate transients pulses is observed. The molecules of COS respond to the terahertz excitation by reradiating a Free Induced Decay (FID) pulses : the molecules absorb the incident pulse and then a periodic rephasing and dephasing of the entire 60 excited equally spaced transitions occurs during the FID.}, \underline{\textbf{66}, (1834),1991}} Therefore the sample emits a series of terahertz pulse at the rate equal to the frequency separation between adjacent lines of 2 B, where B is the rotational constant,. The coherent transient pulse are so observe mainly in the case of linear or symmetric molecules. A model$^b$ based on Maxwell-Bloch equation has been employed to estimate parameters such as the transition linewidth, the rotational and centrifugal distortion constant with the temporal form.
Description
Author Institution: Laboratoire de Physico-Chimie de l'Atmosphere, CNRS UMR-8101,; Universite du Littoral Cote d'Opale, 189A Ave. Maurice; Schumann, 59140 Dunkerque, France