Speaker: Said Rahimzadeh-Kalaleh Rodriguez
Title: Scaling and universality in optical bistability
Abstract: Driven nonlinear dynamical systems can reside in two steady states at a single driving condition. This feature, known as bistability, is associated with emergent phenomena in phase transitions, scaling, and universal behavior. In descriptions of bistable systems, it is typically assumed that the nonlinear force responsible for bistability acts instantaneously on the system. In addition, the role of quantum fluctuations on bistability was until recently largely assumed to be irrelevant to experiments. In this talk, I will present two experiments where these two assumptions were challenged. Both of these experiments were based on nonlinear optical cavities driven by light, but similar physics is expected in other systems. The experiments we performed consisted of scanning a driving parameter (e.g. laser intensity or frequency) across an optical bistability at various speeds, and analyzing the resultant dynamic optical hysteresis. Intriguingly, both quantum fluctuations and non-instantaneous interactions lead to a universal power law decay of the hysteresis area as a function of the scanning speed. However, universal scaling behavior emerges in the opposite limits of slow and fast scans when quantum fluctuations and non-instantaneous interactions are taken into account, respectively. I will conclude with perspectives for realizing lattices of bistable optical cavities, and the opportunities that these bring for performing analog computation and studying non-Markovian nonlinear dynamics with light.
Bio: Said Rodriguez leads the Interacting Photons group at the Center for Nanophotonics in AMOLF. Said got his PhD (Cum Laude) in Applied Physics at the Eindhoven University of Technology, in the former AMOLF/Philips group of Prof. Gómez Rivas. Said’s thesis received the FOM Physics thesis prize – an annual award for the best physics thesis in the Netherlands. Said then received a Marie-Curie fellowship to study quantum and nonlinear optics in the group of Prof. J. Bloch and Dr. A. Amo at the Center for Nanoscience and Nanotechnologies (France). Next, Said did a short postdoc in the group of Prof. A. Mosk at Utrecht University. Throughout this time, Said has worked with various optical systems, including plasmonic lattices, waveguides, organic & inorganic emitters, integrated semiconductor cavities, photonic crystal cavities, and most recently tunable cavities. Said is the recipient of an ERC Starting grant aimed at realizing strongly correlated polaritons in optoelectronic nanostructures. Recently, the Royal Netherlands Academy of Arts and Sciences (KNAW) granted Said the Early Career Award in the domain of Natural and Technical Sciences. Said’s current research interests include stochastic nonlinear dynamics, quantum optics, strong light-matter coupling, sensing, and emergent phenomena in condensed matter systems.