Plasmonic slow light device using superfocusing on a bow-tied metallic waveguide.

We demonstrate a plasmonic slow light device using super focusing on a bow-tied metallic waveguide that can be fabricated using complementary metal-oxide semiconductor compatible processes. By solving the characteristic equation of a bow-tied metallic waveguide, we confirmed that the group indices increased as the waveguide width decreased and that they could attain over 11.0 in the telecommunication wavelength band. Additionally, we experimentally confirmed using an autocorrelation measurement system in which the pulse width of the bow-tied metallic waveguide was 8.0 fs longer than that of a ridged metallic waveguide. Therefore, the proposed device will contribute to the realization of all-plasmonic memories and amplifiers.