Broadband light-matter interaction due to resonance cavities in graded photonic super-crystals

In this paper, we report the formation of resonance cavities within graded photonic super-crystals (GPSCs) with unit cells formed via a near-uniform central region with eight side graded regions. The graded regions in the GPSCs have several photonic band gaps, whereas the uniform region has one photonic band gap. The different locations of the photonic band gaps form a central cavity and eight surrounding side cavities with more cavities at the boundary of the corresponding uniform and graded regions. The quality-factor of the cavities in the boundary regions has been calculated to be as high as 5.8 x 10(5). The central and side cavities have a relatively low-quality factor. Broadband light-matter interaction has been observed in the simulation of transmission through the GPSC. When the thickness of the GPSC is out of resonance with the central cavity mode, the dip in the transmission through the GPSC is shallow and narrow. When the thickness of the GPSC is in-resonance with the central cavity mode, a wide and deep transmission dip is observed in the wavelength range in the photonic band gap of the graded regions. This indicated that the coupling of in-plane resonance in the central region with the Fabry-Perot resonance in the GPSC is occurring. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement