Promotionsvortrag Physik: Kerr-Nonlinearities and Symmetry Breaking in Microresonators

Ankündigung des Promotionsvortrags von: Herrn Alekhya Ghosh

Optical microresonators have positioned themselves as a cornerstone technology for exploring and exploiting nonlinear optics at ultralow threshold powers. The Kerr effect governs the dependence of a medium's refractive index on optical intensity.

This thesis focuses on two distinct nonlinear optical phenomena in Kerr microresonators. The first is spontaneous symmetry breaking (SSB) of light fields, wherein, beyond a critical input power, one of two identically pumped resonant modes acquires a dominant intensity and phase. SSB has promising applications in all-optical computing and precision gyroscopes. The other is the formation of broadband frequency combs, solitons, harmonic generation, and other nonlinear interactions. These phenomena are of significant importance for telecommunications and spectroscopy.

We present theoretical and experimental investigations of several novel Kerr SSB phenomena in single and coupled optical microresonators. We then demonstrate two distinct all-optical switching mechanisms based on symmetry breaking. Next, we discuss fabrication methods and the observation of various novel nonlinear interactions in integrated silicon nitride resonators, including the generation of Raman-Kerr combs, as well as fourth-harmonic UV light generation.

(Vortrag auf Englisch)

Dem Vortrag schließt sich eine Diskussion von 15 Minuten an. Vortrag und Diskussion sind öffentlich. Diesen Verfahrensteilen folgt ein nicht öffentliches Rigorosum von 45 Minuten.