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Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
C-13 Methanol Far-Infrared Laser: Newly Discovered Lines, Predictions, and Assignments
1Departamento de Eletronica Quantica, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, 13083-970, Brazil
Journal of Molecular Spectroscopy
|March 3, 1998
Summary
Researchers discovered 25 new laser lines in methanol (13CH3OH) using a carbon dioxide (CO2) laser. This expands the known far-infrared laser capabilities of methanol for potential applications.
Area of Science:
- Molecular Spectroscopy
- Quantum Electronics
- Far-Infrared Lasers
Background:
- Methanol (13CH3OH) is a molecule with known far-infrared (FIR) laser emission properties.
- Carbon dioxide (CO2) lasers are commonly used as pump sources for molecular lasers.
Purpose of the Study:
- To identify and characterize new laser lines in 13CH3OH.
- To measure the frequencies of these newly discovered and previously reported laser lines.
- To assign specific pump-line relationships for enhanced laser performance.
Main Methods:
- Pumping 13CH3OH molecules with a continuous-wave (cw) CO2 laser.
- Measuring the frequencies of the resulting laser emissions in the far-infrared region.
- Assigning specific CO2 laser lines (e.g., 10R, 10SR, 9HP(20)) as pump sources.
Main Results:
- Reported 25 new laser lines in 13CH3OH.
- Measured 22 laser frequencies, including 19 new lines and 3 previously reported.
- Corrected the frequency of the 9P(44) pumped line to 3 378 404.87 MHz (88.738 μm).
Conclusions:
- Successfully expanded the number of known laser lines for 13CH3OH.
- Identified specific CO2 pump bands (10R, 10SR, 9HP(20)) responsible for new emissions.
- Assigned two specific lines and predicted potential for other FIR laser lines.
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