Free induction decay (FID), optical nutation, and rapid passage induced signals in nitrous oxide, under both optically thin and optically thick conditions, have been observed using a rapid current pulse modulation, or chirp, applied to the slow current ramp of a quantum cascade (QC) laser. The variation in optical depth was achieved by increasing the pressure of nitrous oxide in a long path length multipass absorption cell. This allows the variation of optical depth to be achieved over a range of low gas pressures. Since, even at the highest gas pressure used in the cell, the chirp rate of the QC laser is faster than the collisional reorientation time of the molecules, there is minimal collisional damping, allowing a large macroscopic polarization of the molecular dipoles to develop. This is referred to as rapid passage induced polarization. The resultant FID signals are enhanced due to the constructive interference between the field within the gas generated by the slow ramp of the laser (pump), and that of the fast chirp of the laser (probe) signal generated by pulse modulation of the continuously operating QC laser. The FID signals obtained at large optical depth have not been observed previously in the mid-infrared regions, and unusual oscillatory signals have been observed at the highest gas pressures used.
Skip Nav Destination
,
,
,
Article navigation
7 May 2012
Research Article|
May 07 2012
Observation of infrared free-induction decay and optical nutation signals from nitrous oxide using a current modulated quantum cascade laser Available to Purchase
Geoffrey Duxbury;
Geoffrey Duxbury
1Department of Physics,
University of Strathclyde
, John Anderson Building, 107 Rottenrow, Glasgow G4 0NG, United Kingdom
Search for other works by this author on:
James F. Kelly;
James F. Kelly
2
Pacific Northwest National Laboratory
, PO Box 999, MS K8-88, Richland, Washington 99352, USA
Search for other works by this author on:
Thomas A. Blake;
Thomas A. Blake
2
Pacific Northwest National Laboratory
, PO Box 999, MS K8-88, Richland, Washington 99352, USA
Search for other works by this author on:
Nigel Langford
Nigel Langford
1Department of Physics,
University of Strathclyde
, John Anderson Building, 107 Rottenrow, Glasgow G4 0NG, United Kingdom
Search for other works by this author on:
Geoffrey Duxbury
1
James F. Kelly
2
Thomas A. Blake
2
Nigel Langford
1
1Department of Physics,
University of Strathclyde
, John Anderson Building, 107 Rottenrow, Glasgow G4 0NG, United Kingdom
2
Pacific Northwest National Laboratory
, PO Box 999, MS K8-88, Richland, Washington 99352, USA
J. Chem. Phys. 136, 174317 (2012)
Article history
Received:
August 11 2011
Accepted:
April 10 2012
Connected Content
A companion article has been published:
The ac Stark effect in nitric oxide induced by rapidly swept continuous wave quantum cascade lasers
Citation
Geoffrey Duxbury, James F. Kelly, Thomas A. Blake, Nigel Langford; Observation of infrared free-induction decay and optical nutation signals from nitrous oxide using a current modulated quantum cascade laser. J. Chem. Phys. 7 May 2012; 136 (17): 174317. https://doi.org/10.1063/1.4710540
Download citation file:
Pay-Per-View Access
$40.00
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Citing articles via
CREST—A program for the exploration of low-energy molecular chemical space
Philipp Pracht, Stefan Grimme, et al.
DeePMD-kit v2: A software package for deep potential models
Jinzhe Zeng, Duo Zhang, et al.
Related Content
Time dependent measurements of nitrous oxide and carbon dioxide collisional relaxation processes by a frequency down-chirped quantum cascade laser: Rapid passage signals and the time dependence of collisional processes
J. Chem. Phys. (April 2010)
Collisional Effects On Quantum Cascade Laser Induced Molecular Alignment
AIP Conf. Proc. (October 2010)
Sub-Doppler spectra of infrared hyperfine transitions of nitric oxide using a pulse modulated quantum cascade laser: Rapid passage, free induction decay, and the ac Stark effect
J. Chem. Phys. (May 2012)
Phase-modulated nutation nuclear quadrupole resonance spectroscopy
J. Chem. Phys. (February 1998)
Biexcitonic effect on optical nutation in semiconductor quantum wires
J. Appl. Phys. (November 2004)