Nanoslit-microcavity-based narrow band absorber for sensing applications

• DOI: 10.1364/oe.23.020715
• Publication Date: 2015-07-29T19:05:09Z
• Authors: Xiaoyuan Lu; Lingxuan Zhang; Tongyi Zhang
• Keywords: Figure of Merit

We propose an ultranarrow bandwidth perfect infrared absorber consisting of a metal periodic structured surface with nanoslits, spacer dielectric, and back plate. Its aborption are respectively about 8 nm 95%. The thickness the nanobars spacer, width nanoslits primary factors determining absorption performance. This structure not only has narrow but also can obtain giant electric field enhancement in tiny volume nanoslits. Operated as refractive index sensor, this figure merit high 25. It potential biomedical sensing applications.