Laser for high frequency modulated interferometry
Abstract
A Stark-tuned laser operating in the 119 micron line of CH[sub 3]OH has an output power of several tens of milliwatts at 30 Watts of pump power while exhibiting a doublet splitting of about ten MHz with the application of a Stark field on the order of 500 volts/cm. This output power allows for use of the laser in a multi-channel interferometer, while its high operating frequency permits the interferometer to measure rapid electron density changes in a pellet injected or otherwise fueled plasma such as encountered in magnetic fusion devices. The laser includes a long far-infrared (FIR) pyrex resonator tube disposed within a cylindrical water jacket and incorporating charged electrodes for applying the Stark field to a gas confined therein. With the electrodes located within the resonator tube, the resonator tube walls are cooled by a flowing coolant without electrical breakdown in the coolant liquid during application of the Stark field. Wall cooling allows for substantially increased FIR output powers. Provision is made for introducing a buffer gas into the resonator tube for increasing laser output power and its operating bandwidth. 10 figures.
- Inventors:
- Issue Date:
- OSTI Identifier:
- 7079381
- Patent Number(s):
- 5034952
- Application Number:
- PPN: US 7-446345
- Assignee:
- Dept. of Energy, Washington, DC (United States)
- DOE Contract Number:
- AC02-76CH03073
- Resource Type:
- Patent
- Resource Relation:
- Patent File Date: 5 Dec 1989
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; INTERFEROMETERS; GAS LASERS; PLASMA DIAGNOSTICS; INTERFEROMETRY; THERMONUCLEAR DEVICES; ELECTRON DENSITY; FAR INFRARED RADIATION; MAGNETIC CONFINEMENT; CONFINEMENT; ELECTROMAGNETIC RADIATION; INFRARED RADIATION; LASERS; MEASURING INSTRUMENTS; PLASMA CONFINEMENT; RADIATIONS; 700320* - Plasma Diagnostic Techniques & Instrumentation- (1992-)
Citation Formats
Mansfield, D K, Vocaturo, M, and Guttadora, L J. Laser for high frequency modulated interferometry. United States: N. p., 1991.
Web.
Mansfield, D K, Vocaturo, M, & Guttadora, L J. Laser for high frequency modulated interferometry. United States.
Mansfield, D K, Vocaturo, M, and Guttadora, L J. Tue .
"Laser for high frequency modulated interferometry". United States.
@article{osti_7079381,
title = {Laser for high frequency modulated interferometry},
author = {Mansfield, D K and Vocaturo, M and Guttadora, L J},
abstractNote = {A Stark-tuned laser operating in the 119 micron line of CH[sub 3]OH has an output power of several tens of milliwatts at 30 Watts of pump power while exhibiting a doublet splitting of about ten MHz with the application of a Stark field on the order of 500 volts/cm. This output power allows for use of the laser in a multi-channel interferometer, while its high operating frequency permits the interferometer to measure rapid electron density changes in a pellet injected or otherwise fueled plasma such as encountered in magnetic fusion devices. The laser includes a long far-infrared (FIR) pyrex resonator tube disposed within a cylindrical water jacket and incorporating charged electrodes for applying the Stark field to a gas confined therein. With the electrodes located within the resonator tube, the resonator tube walls are cooled by a flowing coolant without electrical breakdown in the coolant liquid during application of the Stark field. Wall cooling allows for substantially increased FIR output powers. Provision is made for introducing a buffer gas into the resonator tube for increasing laser output power and its operating bandwidth. 10 figures.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1991},
month = {7}
}