We discuss here different strategies for making arrays of Au nanoparticles using copolymer templates. Top-down and
bottom-up routes are considered and the optical properties of as-prepared Au nanoparticles are discussed and compared
to numerical simulations. Potential for applications such as biosensors or strain sensors is also assessed.
In this work, a trilayer graphene is used as a thin non dielectric spacer with a high index of refraction, between Au film
and Au NPs. Encouraged by the sharpness of the localized surface plasmon resonance LSPR induced by this system, we
performed sensitivity measurements to refractive index change in the surrounding medium of the sensor. The presence of
graphene led to both higher sensitivity and sharper full width at half maximum FWHM and thus higher figure of merit
FOM (2.8) compared to the system without graphene (2.1).