Robust Geometries for Second-Harmonic-Generationin Microrings Exhibiting a 4-Bar Symmetry

Year: 2020

Authors: Guillemé P., Vecchi C., Castellan C., Signorini S., Ghulinyan M., Bernard M., Parisi M., Pavesi L.

Autors Affiliation: Nanoscience Laboratory, Departement of Physics, University of Trento, Italy;
Centre for Materials and Microsystems, Fondazione Bruno Kessler, Trento, Italy;
CNR-INO, Istituto Nazionale di Ottica, Italy

Abstract: Microring resonators made of materials with a zinc-blend or diamond lattice allowexploiting their 4-bar symmetry to achieve quasi-phase matching condition for second-order opticalnonlinearities. However, fabrication tolerances impose severe limits on the quasi-phase matchingcondition, which in turn degrades the generation efficiency. Here, we present a method to mitigatethese limitations. As an example, we studied the geometry and the pump wavelength conditions toinduce the second-harmonic generation in silicon-based microrings with a second-order susceptibility χ(2) ≠ 0. We found the best compromises between performances and experimental requirements,and we unveil a strategy to minimize the impacts of fabrication defects. The method can be easilytransferred to other material systems.


Volume: 10      Pages from: 1  to: 12

KeyWords: microrings; second harmonic generation; optical frequency combs
DOI: 10.3390/app10249047