Open AccessSpatially resolved standoff trace chemical sensing using backwards transient absorption spectroscopy
Author(s) -
Fedor Rudakov,
Joseph D. Geiser,
Peter M. Weber
Publication year - 2018
Publication title -
optics letters/optics index
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.524
H-Index - 272
eISSN - 1071-2763
pISSN - 0146-9592
DOI - 10.1364/ol.43.001279
Subject(s) - optics , absorption (acoustics) , materials science , pulse (music) , absorption spectroscopy , spectroscopy , near infrared spectroscopy , ultrafast laser spectroscopy , transient (computer programming) , ultraviolet , temporal resolution , analytical chemistry (journal) , optoelectronics , laser , chemistry , physics , detector , chromatography , quantum mechanics , computer science , operating system
A technique for the spatially resolved and molecule-specific detection of chemical vapors is presented. The chemical specificity arises from a transient absorption spectrum where an ultraviolet (UV) pulse excites the molecule to a Rydberg state, and a near-infrared (NIR) or visible probe pulse records a transient absorption spectrum. By recording the NIR pulse reflected off a random, distant object and measuring the elapsed time between the emission of the UV pulse and the absorption of a counter-propagating NIR pulse, the distance to the absorber is obtained. The feasibility of the approach is demonstrated by detecting acetone plumes with millimeter scale spatial resolution.