A highly tunable biosensor in graphene-vanadium dioxide hyperbolic metamaterial based on surface plasmon resonance

Abstract

We investigate the Goos-Hänchen (GH) shift in a hyperbolic metamaterial (GHMM) comprising graphene and vanadium dioxide (VO2) as the dielectric. Our study reveals that the dispersion type of GHMM can be controlled via Fermi energy of graphene and temperature, modulating wavelength intervals. Notably, the GH shift in type I dispersion surpasses that in elliptical and type II dispersions. This suggests GH shift control by altering dispersion in GHMM. Thickness variations in VO2 and the number of graphene/VO2 layers minimally affect GH shift. In contrast, graphene thickness significantly impacts GH shift, with thicker graphene yielding minor shifts. Meanwhile, we discover that substantial GH shift enhancement by surface plasmon resonance (SPR) excitation, with sensitivity to refractive index changes in the sensing layer. Based on the above conclusions, we theoretically propose a highly tunable biosensor uniting GHMM with SPR and use it to distinguish normal cells from cancer cells. This work advances optical biosensors and precise physical quantity measurements.