Theoretical study on photonic devices based on a commensurate two-pattern photonic crystal

TLDR

In two‑dimensional optical chips, TE and TM modes are distinguished by polarization, and integrating multiple polarization‑specific wave‑control devices on a single wavelength‑scale plane is desirable. The design uses a superposition of two substructures, each providing a TM or TE photonic bandgap, and introduces defects into them to integrate devices that bend, split, and resonate TM and TE waves on the same plane. We demonstrate a periodic two‑pattern photonic crystal that exhibits a large, complete photonic bandgap.

Abstract

In two-dimensional optical chip applications, the optical wave is classified to two modes according to its polarization: TE and TM. It is desirable to integrate multiple optical wave control devices for different polarizations onto the same plane at the scale of the wavelength. Here we demonstrate a periodic two-pattern photonic crystal with a large, complete photonic bandgap (PBG). It comes from the superposition of two substructures: one contributes the TM PBG and the other contributes the TE PBG. By purposely introducing defects into the substructures, photonic devices for different polarizations can be integrated to bend, split, and resonate TM/TE waves simultaneously on the same plane.