Reconfigurable Optical Elements Based on Single and Coupled Microdisk Resonators with Quantum Dot Active Media

Abstract : We report the results of Phase I efforts to realize reconfigurable photonic systems relying on optical bistability in microring and microdisk structures. These reconfigurable systems that can function as optical memory elements are expected to have applications in all-optical signal processors. Hybrid Photonics investigated optical bistable devices based on novel physical principles, which distinguish our efforts from all previously suggested approaches. Two configurations were studied: (i) two active waveguides side coupled to a ring resonator, and (ii) two coupled active microdisk resonators. In both configurations CdSe core-shell quantum dots were used as active gain media. Results of our theoretical efforts at understanding the underlying physical mechanism for the bistability and the modeling efforts to design the bistable device are presented. We also describe the experimental work on the two device configurations and the results obtained. Both the theoretical and experimental work performed indicate the coupled microdisk geometry to be the more practical approach for achieving bistable lasing - a necessary condition for demonstrating an all-optical flip-flop. Finally, we summarize our findings and make recommendations for future work based on our phase 1 results.