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Updated: May 11, 2026

Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation
Published on: February 25, 2017
Nanocavities at the surface of three-dimensional photonic crystals
Kenji Ishizaki1, Kou Gondaira, Yuji Ota
1Department of Electronic Science and Engineering, Kyoto University, Kyoto 615-8510, Japan. ishizaki@qoe.kuee.kyoto-u.ac.jp
Abstract:
We investigate nanocavities at the surface of three-dimensional (3D) photonic crystals, where the polarization-independent surface-mode gap can be utilized. We consider the formation of various nanocavities by introducing artificial defects utilizing the 3D structures around the surface and discuss the possibilities for increasing the Q-factors of the surface nanocavities with TE-like polarization based on the advanced designs of donor-type defects. We also introduce the design of acceptor-type defects and show that TM-like nanocavities are obtained. We then fabricate the designed nanocavities and examine their resonant characteristics; we successfully demonstrate TE-like nanocavities with Q-factors of ~40,000, which is four-times higher than previous surface cavities and as high as that of the cavities embedded inside 3D photonic crystals. TM-like nanocavities with Q-factors of ~22,000 are also demonstrated for the first time.
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