Ultrafast and energy-efficient all-optical switching with graphene-loaded deep-subwavelength plasmonic waveguides

By M. Ono, Masanori Hata, Masato Tsunekawa, Kengo Nozaki, H. Sumikura, H. Chiba, Masaya Notomi. Nature Photonics, 2019

325 citations recorded by the source corpus.

All-optical switches have attracted attention because they can potentially overcome the speed limitation of electric switches. However, ultrafast, energy-efficient all-optical switches have been challenging to realize owing to the intrinsically small optical nonlinearity in existing materials. As a solution, we propose the use of graphene-loaded deep-subwavelength plasmonic waveguides (30 × 20 nm 2 ). Thanks to extreme light confinement, we have greatly enhanced optical nonlinear absorption in graphene, and achieved ultrafast all-optical switching with a switching energy of 35 fJ and a switching time of 260 fs. The switching energy is four orders of magnitude smaller than that in previous graphene-based devices and is the smallest value reported for any all-optical switch operating at a few picoseconds or less. This device can be efficiently connected to conventional silicon waveguides and used in silicon photonic integrated circuits. We believe that this graphene-based device will pave the way towards on-chip ultrafast and energy-efficient photonic processing. All-optical switching with a switching energy of 35 fJ and a switching time of 260 fs is reported in a nanoscale integrated optical circuit.

Subfields: Biomedical Engineering, Electrical and Electronic Engineering

View Paper: https://www.semanticscholar.org/paper/213bdae3e85869191abbbb8de8629da49d58d70c