Files in this item

FilesDescriptionFormat

application/vnd.openxmlformats-officedocument.presentationml.presentation

application/vnd.openxmlformats-officedocument.presentationml.presentation1244864.pptx (2MB)
PresentationMicrosoft PowerPoint 2007

application/pdf

application/pdf3392.pdf (22kB)
AbstractPDF

Description

Title:HIGH-RESOLUTION TERAHERTZ GAIN SPECTRA OF MID-INFRARED PUMPED NH3
Author(s):Lampin, Jean-François
Contributor(s):Postava, Kamil; Vanwolleghem, Mathias; Margulès, L.; Motiyenko, R. A.; Pienkina, A.; Eliet, Sophie; Micica, Martin
Subject(s):Mini-symposium: Far-Infrared Spectroscopy
Abstract:Inversion of population in the terahertz (THz) range can be obtained thanks to the optical pumping of polar molecules in the mid-infrared range. Generally it is done with \chem{CO_2} lasers but recently we have demonstrated the first molecular laser pumped by a quantum cascade laser (QCL). It is based on the optical pumping of the \chem{NH_3} molecule in the \nub{2}=1 state. The gain is obtained by the stimulated emission on pure inversion transitions of \chem{NH_3} (large amplitude motions) around 1 THz that are not accessible to continuous-wave (CW) \chem{CO_2} lasers. We present here CW high-resolution gain measurements of two strong lines: the (3,3) around 1.073 THz and the (4,4) around 1.083 THz. The measurements are done with a THz multiplication chain and an InSb bolometer. The gain profiles are recorded at different pressure and different QCL frequencies as for an IR/THz double resonance experiment. The highest gain at the best conditions are obtained with the (3,3) line: 10 dB/m for a pump power of about 40 mW. To our knowledge this gain is highest measured in the THz range for a CW-pumped molecule. These measurements will help the understanding and the design of our \chem{NH_3} lasers. This kind of laser will find applications in THz molecular spectroscopy/astronomy as a source or as a local oscillator for heterodyne detection.
Issue Date:06/20/18
Publisher:International Symposium on Molecular Spectroscopy
Citation Info:APS
Genre:Conference Paper / Presentation
Type:Text
Language:English
URI:http://hdl.handle.net/2142/100746
DOI:10.15278/isms.2018.WI04
Other Identifier(s):WI04
Date Available in IDEALS:2018-08-17
2018-12-12


This item appears in the following Collection(s)

Item Statistics