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Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
Near-infrared diode laser spectrometer with frequency calibration using internal second harmonics.
Applied Optics
|August 14, 2010
Summary
High-accuracy frequency calibration was achieved for a 1.3-microm diode laser spectrometer using iodine molecule spectra. This method provides an absolute accuracy of 0.002 cm(-1) for precise measurements.
Area of Science:
- Spectroscopy
- Laser Physics
- Metrology
Background:
- Precise frequency calibration is crucial for spectroscopic measurements.
- Diode laser spectrometers require accurate frequency standards for reliable data acquisition.
- Existing calibration methods may have limitations in accuracy or applicability.
Purpose of the Study:
- To develop a high-accuracy frequency calibration method for a 1.3-microm diode laser spectrometer.
- To utilize the iodine molecule's visible spectrum as an internal frequency standard.
- To improve the precision of spectroscopic measurements in the near-infrared region.
Main Methods:
- Frequency calibration using internal second harmonics of a 1.3-microm diode laser.
- Simultaneous recording of the iodine molecule's visible spectrum.
- Employing an étalon for frequency markers to achieve absolute accuracy.
- Remesuring atomic and molecular transitions in the near-infrared region.
Main Results:
- Achieved an absolute accuracy of 0.002 cm(-1) for frequency calibration.
- Successfully used the iodine molecule's visible spectrum as a reliable frequency standard.
- Demonstrated the effectiveness of the method for remeasuring near-infrared transitions.
Conclusions:
- The developed method offers a precise and efficient way to calibrate diode laser spectrometers.
- The use of internal second harmonics and iodine spectra provides a robust frequency reference.
- This technique enhances the accuracy of measurements for various atomic and molecular transitions.
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