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Construction and Characterization of External Cavity Diode Lasers for Atomic Physics
Published on: April 24, 2014
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Delay induced high order locking effects in semiconductor lasers
B Kelleher1, M J Wishon2, A Locquet2
1Department of Physics, University College Cork, Cork, Ireland.
Chaos (Woodbury, N.Y.)
|December 3, 2017
Summary
Optical feedback in semiconductor lasers introduces a new time scale, enabling resonances with relaxation oscillations. This phenomenon leads to spontaneous mode-locking in lasers with highly damped oscillations, confirmed in quantum dot and quantum well devices.
Area of Science:
- Nonlinear Dynamics
- Semiconductor Laser Physics
- Photonics
Background:
- Nonlinear dynamical systems often exhibit multiple time scales.
- Semiconductor lasers possess intrinsic time scales: cavity repetition rate and relaxation oscillation frequency.
- Optical feedback introduces an external cavity repetition rate, a significantly longer time scale.
Purpose of the Study:
- To investigate the impact of optical feedback on semiconductor laser dynamics.
- To explore the potential for resonances between relaxation oscillations and the external cavity repetition rate.
- To demonstrate spontaneous mode-locking induced by these resonances.
Main Methods:
- Experimental analysis of quantum dot and quantum well semiconductor lasers.
- Inclusion of optical feedback to introduce an external cavity time scale.
- Theoretical modeling using a rate equation approach.
Main Results:
- Resonances between relaxation oscillations and the external cavity repetition rate were achieved in lasers with highly damped oscillations.
- Spontaneous mode-locking was observed as a direct consequence of these resonances.
- Experimental results from quantum dot and quantum well lasers showed qualitatively identical dynamics.
- A rate equation model demonstrated excellent agreement with experimental findings.
Conclusions:
- Optical feedback is a viable method to induce resonances and spontaneous mode-locking in semiconductor lasers.
- The dynamics are consistent across different semiconductor laser types (quantum dot and quantum well).
- Rate equation models accurately capture the observed multiple time scale dynamics and mode-locking phenomena.
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