Skip to content
University of Maryland LibrariesDigital Repository at the University of Maryland
    • Login
    View Item 
    •   DRUM
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • View Item
    •   DRUM
    • Theses and Dissertations from UMD
    • UMD Theses and Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    DELAY INDUCED INSTABILITIES IN COUPLED SEMICONDUCTOR LASERS AND MACKEY-GLASS ELECTRONIC CIRCUITS

    Thumbnail
    View/Open
    umi-umd-2668.pdf (8.821Mb)
    No. of downloads: 1318

    Date
    2005-07-25
    Author
    Kim, Min-Young
    Advisor
    Roy, Rajarshi
    Metadata
    Show full item record
    Abstract
    We describe two experimental systems where a time-delayed feedback mechanism plays an important role in inducing instabilities. The first system consists of two cross-coupled semiconductor lasers with time-delayed negative optoelectronic feedback. This system is described by coupled delay-differential equations, and we explore the dynamics near the onset of oscillations as the coupling strength is varied. We study the influence of asymmetric coupling strengths on the onset of oscillations and the dependence of the amplitudes of oscillations on the coupling strengths. In-phase oscillations with a period of twice the delay time emerge as the product of coupling strengths increases above a critical value. A scaling relationship is observed between rescaled amplitudes of oscillations and the product of the coupling strengths. We also study the dependence of the periodicity and the phase relations of the oscillations as we adjust the delay time. The second system is an electronic circuit with time-delayed nonlinear feedback which simulates the Mackey-Glass model described by a delay-differential equation. First we study the dynamics of the Mackey-Glass system in various parameter regimes and then we study the synchronization of two unidirectionally coupled Mackey-Glass circuits. The change of the quality of the synchronization with parameter mismatch as well as bandwidth limitations in the transmission channel is investigated. With a low pass filter in the transmission line, we find that the inclusion of the dominant frequency component of the original driver signals is crucial to achieve synchronization between the driver and receiver circuits, both numerically and experimentally.
    URI
    http://hdl.handle.net/1903/2722
    Collections
    • Physics Theses and Dissertations
    • UMD Theses and Dissertations

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility
     

     

    Browse

    All of DRUMCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

    My Account

    LoginRegister
    Pages
    About DRUMAbout Download Statistics

    DRUM is brought to you by the University of Maryland Libraries
    University of Maryland, College Park, MD 20742-7011 (301)314-1328.
    Please send us your comments.
    Web Accessibility