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Construction and Characterization of External Cavity Diode Lasers for Atomic Physics
Published on: April 24, 2014
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A low-temperature external cavity diode laser for broad wavelength tuning
William G Tobias1, Jason S Rosenberg1, Nicholas R Hutzler1
1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
The Review of Scientific Instruments
|December 3, 2016
Summary
This study presents a novel low-temperature external cavity diode laser (ECDL) system for broad wavelength tuning. The system overcomes the scarcity of red laser diodes below 633 nm, enabling new spectroscopic applications.
Area of Science:
- Laser Physics
- Spectroscopy
- Optical Engineering
Background:
- Commercial red laser diodes below 633 nm are scarce, limiting spectroscopic studies.
- This wavelength range is crucial for analyzing many molecules and ions.
Purpose of the Study:
- To design and characterize a low-temperature external cavity diode laser (ECDL) system.
- To achieve broad wavelength tuning, particularly in the under-served red spectrum.
- To address the limitations of existing commercial laser diodes.
Main Methods:
- Utilized a combination of multi-stage thermoelectric and water cooling to reach -64°C.
- Integrated temperature and diffraction grating feedback for precise wavelength control.
- Tested multiple diode laser models for performance evaluation.
Main Results:
- Achieved single-mode operation with 38 mW at 616.8 nm and 69 mW at 622.6 nm.
- Tuned diodes more than 15 nm below their free-running wavelengths.
- Demonstrated broad continuous tuning over tens of nanometers for individual diodes.
Conclusions:
- The developed low-temperature ECDL system effectively extends the wavelength coverage of commercial laser diodes.
- This technology enables new spectroscopic investigations requiring specific red wavelengths.
- The ECDL design is adaptable for various diode laser wavelengths.
