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Construction and Characterization of External Cavity Diode Lasers for Atomic Physics
Published on: April 24, 2014
Extending the continuous tuning range of an external-cavity diode laser
Kevin S Repasky1, Amin R Nehrir, Justin T Hawthorne
1Department of Electrical and Computer Engineering, Cobleigh Hall, Room 610, Montana State University, Bozeman, Montana 59717, USA. repasky@ece.montana.edu
Applied Optics
|November 23, 2006
Summary
An electronic feedback loop extends the continuous tuning range of external-cavity diode lasers by maintaining resonance conditions. This method eliminates mode hops, enabling a tuning range over 65 GHz.
Area of Science:
- Laser Physics
- Optical Engineering
Background:
- External-cavity diode lasers (ECDLs) typically have limited continuous tuning ranges due to mode hops.
- Maintaining cavity resonance is crucial for achieving broader tuning capabilities.
Purpose of the Study:
- To design and demonstrate an external-cavity diode laser with an extended continuous tuning range.
- To investigate the effectiveness of an electronic feedback loop in overcoming mode hop limitations.
Main Methods:
- Utilized a Littman-Metcalf external-cavity diode laser configuration.
- Implemented an electronic feedback loop employing a lock-in amplifier to control external-cavity length.
- Introduced a sinusoidal modulation to the laser diode drive current for phase comparison.
Main Results:
- Achieved a continuous tuning range of 1 GHz without electronic feedback.
- Extended the continuous tuning range to over 65 GHz with the electronic feedback loop.
- Demonstrated the extended tuning range by scanning through a diatomic oxygen absorption feature near 760 nm.
Conclusions:
- Electronic feedback effectively maintains cavity resonance, eliminating mode hops and significantly broadening the tuning range of ECDLs.
- The developed system offers a practical solution for applications requiring wide, continuous wavelength tuning in diode lasers.
