Plasmonic enhanced optical coupling effect on the quantum well infrared photodetector

We propose a novel structure to couple quantum well infrared photodetectors (QWIPs) by inserting a gold disk array into the interface between gold and dielectric layers. The periodic plasmonic effect of the gold disks together with the cavity effect of the finite-thickness dielectric layer enables the incident light field to concentrate at the location of quantum wells, which is proved by the finite element simulation. This will largely facilitate the design and processing of the QWIPs to employ plasmonic enhancement effect where the near field effects are usually involved. We believe that this structure provide a new solution to improve the performance of QWIPs.