Files in this item

FilesDescriptionFormat

application/vnd.openxmlformats-officedocument.presentationml.presentation

application/vnd.openxmlformats-officedocument.presentationml.presentation481504.pptx (4MB)
PresentationMicrosoft PowerPoint 2007

application/pdf

application/pdf1312.pdf (21kB)
AbstractPDF

Description

Title:QUANTUM-NOISE-LIMITED CAVITY RING-DOWN SPECTROSCOPY IN THE MID-INFRARED
Author(s):Fleisher, Adam J.
Contributor(s):Hodges, Joseph; Liu, Qingnan; Long, David A.
Subject(s):Mini-symposium: High-Precision Spectroscopy
Abstract:We report a highly sensitive mid-infrared spectrometer capable of recording cavity ring-down events in the quantum (shot) noise limit. A linear optical cavity of finesse 31,000 was pumped by a distributed feedback quantum cascade laser (DFB-QCL) operating at 4.5 $mu$m until a cavity transmission threshold was reached. A fast optical switch then extinguished optical pumping and initiated a cavity decay which exhibited root-mean-square noise proportional to the square root of optical power (quantum noise) for several cavity time constants until a detector noise floor was reached. This spectrometer has achieved a noise-equivalent absorption of NEA = $2.6times10^{-11}$ wn Hz$^{-1/2}$ and a minimum absorption coefficient of $alpha = 2.3times10^{-11}$ wn in 3 seconds. Applications for such a highly sensitive spectrometer operating in the mid-infrared region, including ultra-trace molecular spectroscopy of chem{CO_2} isotopologues and the direct interrogation of weak mirror birefringence and polarization-dependent losses, will be discussed.
Issue Date:24-Jun-15
Publisher:International Symposium on Molecular Spectroscopy
Citation Info:ACS
Genre:CONFERENCE PAPER/PRESENTATION
Type:Text
Language:English
URI:http://hdl.handle.net/2142/79390
Date Available in IDEALS:2016-01-05


This item appears in the following Collection(s)

Item Statistics