Complete crossing of Fano resonances in an optical microcavity via nonlinear tuning
Authors: Bernard M., Manzano FR., Pavesi L., Pucker G., Carusotto I., Ghulinyan M.
Autors Affiliation: Fdn Bruno Kessler, Ctr Mat & Microsyst, I-38123 Povo, Italy; Univ Trento, Dept Phys, Nanosci Lab, I-38123 Povo, Italy; Univ Trento, INO CNR BEC Ctr, I-38123 Povo, Italy; Univ Trento, Dept Phys, I-38123 Povo, Italy
Abstract: We report on the modeling, simulation, and experimental demonstration of complete mode crossings of Fano resonances within chip-integrated microresonators. The continuous reshaping of resonant line shapes is achieved via nonlinear thermo-optical tuning when the cavity-coupled optical pump is partially absorbed by the material. The locally generated heat then produces a thermal field, which influences the spatially overlapping optical modes, allowing us to alter the relative spectral separation of resonances. Furthermore, we exploit such tunability to continuously probe the coupling between different families of quasi-degenerate modes that exhibit asymmetric Fano interactions. As a particular case, we demonstrate a complete disappearance of one of the modal features in the transmission spectrum as predicted by Fano [Phys. Rev. 124, 1866 (1961)]. The phenomenon is modeled as a third-order nonlinearity with a spatial distribution that depends on the stored optical field and thermal diffusion within the resonator. The performed nonlinear numerical simulations are in excellent agreement with the experimental results, which confirm the validity of the developed theory. (C) 2017 Chinese Laser Press
Journal/Review: PHOTONICS RESEARCH
Volume: 5 (3) Pages from: 168 to: 175
KeyWords: ELECTROMAGNETICALLY INDUCED TRANSPARENCY; SILICON MICRORING RESONATORS; GALLERY-MODE RESONATORS; WAVE-GUIDES; LOW-POWER; PHOTONICS; CHIPDOI: 10.1364/PRJ.5.000168Citations: 8data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2021-10-24References taken from IsiWeb of Knowledge: (subscribers only)Connecting to view paper tab on IsiWeb: Click hereConnecting to view citations from IsiWeb: Click here