Stimulated Raman Scattering in Methane with Nd:YAG Pump.
Abstract
The results of an experimental study of stimulated Raman scattering in methane pumped by a repetitively Q-switched Nd:YAG laser are presented and discussed. Three compact geometrical arrangements were investigated: (1) Raman cell external to the laser cavity with focusing and recollimating optics, (2) Raman cell External to cavity with pump beam coupled into a leaky waveguide (pyrex capillary) immersed in high pressure methane, and (3) Raman cell positioned internal to laser cavity. In configurations (1) and (2), photon conversion efficiencies from 1.06 micrometers to 1.54 micrometers of 15% to 20% were observed with good amplitude stability if proper attention is given to laser adjustment. These results are based on direct measurements of the various signals; pump depletion measurements can not be used to infer energy conversion from pump to Stokes unless care is taken to eliminate pump backscatter. Configuration (3) produced 6.8 millijoule Stokes pulses of 8 nanosecond total width between half power points with remarkable amplitude and shape stability. With careful engineering this basic configuration would be feasible for designing a 1.54 micrometers rangefinder or illuminator.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1977
- Accession Number
- ADA042391
Entities
People
- J. G. Meadors
- M. A. Poirier
Organizations
- Ohio State University