Asymmetric Fabry-Perot cavity based perfect absorber for infrared spectroscopic devices

摘要

Artificial subwavelength structures such as plasmonic perfect absorbers, metallic gratings and photonic crystals have been proposed to tailor the spectral absorption for spectroscopic devices. Though, the subwavelength scalability constraints of these patterned structures require high-precision and multi-stage lithography. Facilitated by rapid progress in thin film deposition techniques, importance of multilayer planar films to achieve near-unity absorption for large-area surfaces have been recently reinvigorated. Among many types of layered structures, asymmetric Fabry-Perot (FP) cavity structures have shown distinct advantage of tunability and high-resolution spectroscopy due to their strict resonant condition of multiple interference.