Ph.D. Dissertation Defense - Daeyoung Choi

Event Details

Monday, July 2, 2018

10:30am - 12:30pm

Room 412A, Tech Tower

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Event Details

TitleIntermittent Dynamics of an External-Cavity Semiconductor Laser


Dr. David Citrin, ECE, Chair , Advisor

Dr. Alexandre Locquet, GTL, Co-Advisor

Dr. Robert Butera, ECE

Dr. Douglas Williams, ECE

Dr. Paul Yoder, ECE

Dr. Kurt Wiesenfeld, Physics


The main objective in this thesis is to investigate experimentally nonlinear dynamical behaviors of an external-cavity semiconductor laser (ECSL) when it is subjected to timedelayed optical feedback with various operating parameters. Systematic information concerning the dynamical regimes and the bifurcations between them will be introduced by bifurcation diagrams (BDs). By means of BDs, we provide a global picture of the dynamical system and systematic investigations of the rich variety of dynamical behaviors observed in ECSLs. While obtaining several experimental BDs, we find that there are intermittent phenomena between dynamical regimes. When an ECSL is operated at low injection current slightly above threshold, we can observe intermittency between stationary operation and low frequency fluctuations. Some of those fluctuations in intermittency lead to extremely high pulsations. In addition, we investigate multistate intermittency, and intermittency between period-doubled dynamics and fully developed coherence collapse when the ECSL is operated at higher injection current. We characterize statistically these intermittencies and compare with other types of intermittency observed in different dynamical systems. However, when ECSLs exhibit the continuous wave operation without interrupted by intermittent or irregular dynamics, we suggest a simple and compact ECSL application that is possible to detect displacement of the remote target with a few tens-of-nanometers resolution.

Last revised June 15, 2018