Open AccessUltralow-energy and high-contrast all-optical switch involving Fano resonance based on coupled photonic crystal nanocavities
Author(s) -
Kengo Nozaki,
Akihiko Shinya,
Shinji Matsuo,
Tomonari Sato,
Eiichi Kuramochi,
Masaya Notomi
Publication year - 2013
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.21.011877
Subject(s) - fano resonance , optical switch , photonic crystal , optics , optoelectronics , contrast ratio , resonance (particle physics) , photonics , energy (signal processing) , slow light , nanophotonics , bandwidth (computing) , materials science , contrast (vision) , physics , telecommunications , plasmon , atomic physics , quantum mechanics , computer science
We experimentally and theoretically clarified that a Fano resonant system based on a coupled optical cavity has better performance when used as an all-optical switch than a single cavity in terms of switching energy, contrast, and operation bandwidth. We successfully fabricated a Fano system consisting of doubly coupled photonic-crystal (PhC) nanocavities, and demonstrated all-optical switching for the first time. A steep asymmetric transmission spectrum was clearly observed, thereby enabling a low-energy and high-contrast switching operation. We achieved the switching with a pump energy of a few fJ, a contrast of more than 10 dB, and an 18 ps switching time window. These levels of performance are actually better than those for Lorentzian resonance in a single cavity. We also theoretically investigated the achievable performance in a well-designed Fano system, which suggested a high contrast for the switching of more than 20 dB in a fJ energy regime.