Electromagnetically induced transparency in all-dielectric metamaterial-waveguide system

Abstract

We demonstrate theoretically an analogue of electromagnetically induced transparency (EIT) at visible frequencies in an all-dielectric metamaterial-waveguide (ADMW) system that consists of a two-dimensional silicon nanopillar array on top of a dielectric slab waveguide. By varying the lattice period of the array, we show that the transmission feature of the hybridized ADMW system can be efficiently engineered due to the period-dependent guided modes. For ADMW systems with different lattice periods, the EIT-like transparency windows are confirmed either from the two detuned guided modes in the waveguide layer or from the Fano-type interference between the guided modes and the magnetic dipole mode in silicon nanopillars. We have also demonstrated the significant electric field enhancement in the waveguide layer and the remarkable slow-light effect associated with the EIT-like transmission. Compared with the hybrid waveguide-plasmon system including a metal-resonator array, the silicon-based ADMW system enables production of high Q-factor resonances with low absorption losses, thereby having promising applications in low-loss slow-light devices, bio/chemical sensing, enhancing emission rate, and optical modulation.