[19a-Z10-1~10] 3.11 Photonic structures and phenomena

△ [19a-Z10-7] Design of Broadband Diplexer using Valley Photonic Crystals

〇Kei Iyoda¹, Yuichiro Yamagami¹, Masayuki Fujita¹, Tadao Nagatsuma¹ (1.Osaka Univ.)

Keywords:Valley Photonic Crystals

We present a heterogenous coupled-line filter structure that is based on interaction between the bearded- and zig-zag topological insulator states of valley photonic crystal. We show that this structure serves as an efficient, compact, and broadband integrated diplexer whose isolation is enhanced by a photonic bandgap that is exhibited by the heterogeneous coupled-line structure. The bandwidth of present diplexer is more than twice that of a photonic crystal diplexer previously reported.