Silicon photonic crystal heterojunctions based dual-band unidirectional transmission with high transmissivity

摘要

Heterojunctions, which consist of two-dimensional circular- and square- hole silicon photonic crystals (PCs), are presented. Based on the finite-different time-domain simulations, the light transmission spectra and field distributions are obtained. A dual-band efficient unidirectional transmission behavior is realized by exciting higher diffraction orders through the novel interface structure. Owing to the self-collimation effect, high-quality unidirectional beam splitting phenomena are also observed. A heterojunction, which can achieve both dual-band unidirectional transmission with high transmissivity of 86.7% and two high-intensity good-directionality split beams, is constructed.