Design analysis of hybrid silicon-on-nothing photonic crystal-nanoantenna structures for engineering of midinfrared radiative properties
Date of Original Version
Electromagnetic (EM) behaviors of photonic crystals (PhCs) and nanoantenna (NA) arrays have been extensively studied and applied to a myriad of applications, including light absorption, surface-enhanced Raman scattering, light trapping in photovoltaics, and spectral narrowing of thermal emission. However, not many works have studied the integration of three-dimensional (3-D) PhCs and NA arrays into one structure mainly due to technical challenges in manufacturing 3-D PhCs. The present article reports the design analysis of a hybrid optical structure that has a gold rectangular NA array aligned on a 3-D silicon-on-nothing (SON) PhC substrate. By applying a continuous phase field model, we numerically simulate the formation of SON-PhC structures (i.e., a 3-D periodic array of spherical voids in silicon) during the high-Temperature annealing process of a silicon substrate having vertical trenches. Photonic behaviors of the NA-on-SON PhC structure are computed using the finite-difference time-domain method. The obtained results exhibit the resonant absorption of midinfrared (mid-IR) light in the stopping bands of the SON-PhC (3.0μm<λ<7.5μm) by photon coupling with the free electron oscillations in each NA structure. This PhC-mediated NA resonance is manifested by highly concentrated electric fields at NA corners; the corresponding local field enhancement factor is one order of magnitude greater than that of the NA array on a bare silicon substrate.
Publication Title, e.g., Journal
Journal of Nanophotonics
Jensen, Devon, Jihwan Song, Dongchoul Kim, Jungchul Lee, Geofferey D. Bothun, Arijit Bose, and Keunhan Park. "Design analysis of hybrid silicon-on-nothing photonic crystal-nanoantenna structures for engineering of midinfrared radiative properties." Journal of Nanophotonics 12, 2 (2018). doi: 10.1117/1.JNP.12.026005.