GST plasmonic gap structure investigation as a switch and sensor

Abstract

In this paper, a plasmonic perfect absorber that consists of a gold rectangular bar with three gaps is investigated as a switch and sensor in the near-infrared region. Phase change material germanium–antimony–tellurium (GST) is utilized in two gaps to perform the switching capability with a high extinction ratio of 18.49 dB. In addition, the sensing performance of the structure for detection of a solution of glucose in water and diagnosis of different cancer cells is studied. The best sensitivity of 1504 nm/RIU is obtained for detection of the PC12 cancer cell, and the figure of merit of the structure is around 17RIU−1.