Imaging characterization of the rapid adiabatic passage in a source-rotatable, crossed-beam scattering experiment

In order to achieve a more efficient preparation of a specific ro-vibrationally excited reactant state for reactive scattering experiments, we implemented the rapid adiabatic passage (RAP) scheme to our pulsed crossed-beam machine, using a single-mode, continuous-wave mid-infrared laser. The challen...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of chemical physics 2017-07, Vol.147 (1), p.013928-013928
Main Authors: Pan, Huilin, Mondal, Sohidul, Yang, Chung-Hsin, Liu, Kopin
Format: Article
Language:English
Subjects:
Adiabatic flow
Continuous wave lasers
Infrared lasers
Laser beams
Lasers
Molecular beams
Optical Parametric Oscillators
Parametric amplifiers
Scattering
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:In order to achieve a more efficient preparation of a specific ro-vibrationally excited reactant state for reactive scattering experiments, we implemented the rapid adiabatic passage (RAP) scheme to our pulsed crossed-beam machine, using a single-mode, continuous-wave mid-infrared laser. The challenge for this source-rotatable apparatus lies in the non-orthogonal geometry between the molecular beam and the laser propagation directions. As such, the velocity spread of the supersonic beam results in a significantly broader Doppler distribution that needs to be activated for RAP to occur than the conventional orthogonal configuration. In this report, we detail our approach to shifting, locking, and stabilizing the absolute mid-infrared frequency. We exploited the imaging detection technique to characterize the RAP process and to quantify the excitation efficiency. We showed that with appropriate focusing of the IR laser, a nearly complete population transfer can still be achieved in favorable cases. Compared to our previous setup—a pulsed optical parametric oscillator/amplifier in combination with a multipass ring reflector for saturated absorption, the present RAP scheme with a single-pass, continuous-wave laser yields noticeably higher population-transfer efficiency.
ISSN:0021-9606
1089-7690
DOI:10.1063/1.4982615