Study of the sensitivity of Au@Cu2−xS conical nanoshell sensors based on localized surface plasmons.

To investigate nanosensors based on localized surface plasmon, a structure consisting of a conical nanoshell has been considered and the factors affecting its performance has been studied. The factors are the refractive index of the background environment, dimensions, and the nanoshell material. A nanosensor consisting of an Au@Cu_2−xS nanoshell with a Cu_2−xS semiconductor shell and a gold core has been proposed and its sensitivity has been investigated. The sensitivity of this Cu_2−xS nanoshell reaches 1505 nm RIU , which is more than bimetallic nanoshells. Using the boundary element method and calculating the extinction cross-section in terms of wavelength, the dependence of the resonance wavelength of the localized surface plasmon on different parameters has been investigated. It is shown that the nanosensor investigated in this research has a high sensitivity to the changes in the refractive index of the studied sample. In addition, the required spectral range can be arbitrarily adjusted by the type of nanoparticles. [ABSTRACT FROM AUTHOR]