Mode Medium Interaction In Continuous Wave (CW) Flowing Gas Lasers

E. R. Peressini; C. G. Parazzoli

doi:10.1117/12.956226

17 August 1978 Mode Medium Interaction In Continuous Wave (CW) Flowing Gas Lasers

E. R. Peressini, C. G. Parazzoli

Proceedings Volume 0138, Advances in Laser Technology III: Emphasizing Gaseous Lasers; (1978) https://doi.org/10.1117/12.956226
Event: 1978 Technical Symposium East, 1978, Washington, D.C., United States

Abstract

A general nonlinear treatment of mode medium interaction in CW flowing gas lasers is presented. Mode medium interaction is the term which has been used to refer to the dynamic process of extracting optical energy from an excited laser medium. The nonlinear theory describes the coupling between the excited medium perturbation due to optical power extraction and the optical system controlling the power extraction. The nonlinear theory shows that, while a significant mode medium interaction can exist in large scale devices, no acoustic instability is predicted. This prediction is contrasted with results obtained from a conventional linear instability analysis of the same system which erroneously suggests an acoustic instability such that beyond a small threshold value, medium and optical power disturbances are amplified to instability. The underlying reasons for the breakdown of the linearized theory are described. Scaling relations developed from the nonlinear theory are also presented to establish that high quality large scale CW flowing gas lasers are feasible. The paper is theoretically oriented; however, some supporting experimental data is presented. In addition to the nonlinear stability analysis, an accurate description of cross-flow medium acoustics is developed, which properly accounts for the bulk heat input into the flowing medium. It is shown that the pressure gradient, produced in the flow direction by the medium bulk heating, strongly damps the buildup of cross-flow acoustic disturbances.

Citation Download Citation

E. R. Peressini and C. G. Parazzoli "Mode Medium Interaction In Continuous Wave (CW) Flowing Gas Lasers", Proc. SPIE 0138, Advances in Laser Technology III: Emphasizing Gaseous Lasers, (17 August 1978); https://doi.org/10.1117/12.956226

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available