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Construction and Characterization of External Cavity Diode Lasers for Atomic Physics
Published on: April 24, 2014
Widely tunable coupled-cavity semiconductor laser
Ferdous K Khan1, Daniel T Cassidy
1Department of Engineering Physics, McMaster University, JHE-A315, 1280 Main Street West, Hamilton, Ontario L8S 4L8, Canada. khanfk@mcmaster.ca
Applied Optics
|July 3, 2009
Summary
Researchers developed a tunable semiconductor laser with 100 nm tuning. Device performance was improved by analyzing below-threshold spectra using a transfer matrix model, revealing distinct operational modes based on facet angles.
Area of Science:
- Optics and Photonics
- Semiconductor Devices
- Laser Technology
Background:
- Tunable semiconductor lasers are crucial for various applications, including spectroscopy and optical communications.
- Coupled-cavity semiconductor lasers offer potential for enhanced tuning capabilities.
- Understanding the operational dynamics of these devices is key to optimizing their performance.
Purpose of the Study:
- To describe a widely tunable coupled-cavity semiconductor laser with a tuning range of approximately 100 nm.
- To develop and present a below-threshold model for coupled-cavity devices using a transfer matrix approach.
- To extract device parameters and understand operational modes for performance improvement.
Main Methods:
- Development of a below-threshold model incorporating facet tilt using a transfer matrix approach.
- Application of nonlinear fits to below-threshold spectra for device parameter extraction.
- Analysis of device operation based on extracted parameters and facet angles.
Main Results:
- A coupled-cavity semiconductor laser with a nearly continuous tuning capability of approximately 100 nm was demonstrated.
- The developed model accurately fits experimental below-threshold spectra, enabling parameter extraction.
- Facet angles significantly influence device operation: > or = 7 degrees leads to injection-locked behavior, while < or = 4 degrees results in a truly-coupled system.
Conclusions:
- The transfer matrix model provides valuable insights into coupled-cavity semiconductor laser operation.
- Device performance can be optimized by controlling facet angles to achieve desired operational modes.
- This work contributes to the advancement of widely tunable semiconductor laser technology.
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