Comparison of Localised Surface Plasmon Resonance and Refractive Index Sensitivity for metallic nanostructures

Abstract

Abstract Metal nanoparticles support strong and tunable surface plasmon resonance in deep UV-visible-NIR region. In this paper, the comparative study of localised surface plasmon resonance and refractive index sensitivity between metallic (Au, Ag and Al) nanostructures is done which serve as a guide in making the optimum choice for a low-loss plasmonic material in various applications mainly plasmonic sensor. The spectra obtained by Finite Difference Time Domain solutions clearly confirm that the LSPR of Al lies in the shorter wavelength as compared to Au and Ag but variation in geometrical parameter has explored the Al nanoparticle over deep-UV-NIR region. The new strategies by coating the nanoparticles forming layered nanostructure to maintain the stability of the nanostructure is discussed. These nanostructures support strong and tunable LSPR as well as high RIS factor of 510 nm/RIU and 470 nm/RIU for Al–Air–Au and Ag-Air-Au, respectively.