A wide wavelength range optical switch using a flexible photonic crystal waveguide and silicon rods

摘要

We theoretically and experimentally demonstrated that the transmittance of a two-dimensional photonic crystal waveguide (PCW) can be controlled in the 90 nm wavelength range by changing the difference in height between the PCW and silicon column rods that have the same central axis and height as the PCW air holes. Simulations conducted with a three-dimensional finite difference time domain method showed that the transmittance change of a PCW with four air holes in the light propagating direction was -8.5 dB when the height difference was only half the thickness of the slab. We fabricated an optical switch on a single chip by using a single-mask three-step process that consists of electron beam lithography, inductive coupled plasma reactive ion etching and release with hydrofluoric acid vapor. We measured -4.4 dB attenuations at wavelengths ranging from 1470 to 1500 nm.