Open AccessPerformance of a high-resolution mid-IR optical-parametric-oscillator transient absorption spectrometer
Author(s) -
Geraldine O. Echebiri,
Matthew D. Smarte,
Wendell W. Walters,
Amy S. Mullin
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.014885
Subject(s) - optical parametric oscillator , optics , spectrometer , ultrafast laser spectroscopy , absorption (acoustics) , materials science , absorption spectroscopy , tunable diode laser absorption spectroscopy , laser , wavelength , noise (video) , physics , atomic physics , artificial intelligence , computer science , image (mathematics)
We report on a mid-IR optical parametric oscillator (OPO)-based high resolution transient absorption spectrometer for state-resolved collisional energy transfer. Transient Doppler-broadened line profiles at λ = 3.3 μm are reported for HCl R7 transitions following gas-phase collisions with vibrationally excited pyrazine. The instrument noise, analyzed as a function of IR wavelength across the absorption line, is as much as 10 times smaller than in diode laser-based measurements. The reduced noise is attributed to larger intensity IR light that has greater intensity stability, which in turn leads to reduced detector noise and better frequency locking for the OPO.