Gires-Tournois interferometer based on the self-collimation effect in a two-dimensional photonic crystal

Abstract A photonic crystal Gires-Tournois interferometer (PCGTI) based on the self-collimation effect in two-dimensional photonic crystal (PC) is proposed and numerically investigated using finite-difference time-domain (FDTD) simulations. The PCGTI is composed of two 100% reflecting mirrors, a partially reflecting mirror and a beam splitter. Both of hole-type and rod-type PCGTIs have rectangular-shaped transmission spectra. So, they can work as bandpass/bandstop filters with appropriate structure parameters. If the central normalized frequency corresponds to 1550 nm, the TE bandpass and bandstop bandwidths for the hole-type PCGTI are 15 nm and 18 nm respectively, while the TM bandpass and bandstop bandwidths for the rod-type PCGTI are both 20 nm. As its size is on the order of 10 micrometers, the PCGTI may have potential applications in the future photonic integrated circuits.