Broadband, Non-resonant Platform for Electric field Enhancement

Electric field enhancement over nanoscale volumes can typically be achieved by exploiting resonant phenomena such as structural surface plasmons in metals. Electric field enhancement is a key component in manipulating electromagnetic behavior impacting several phenomena such as sensing, light emission and non-linearity. However, their operational bandwidth is limited by the resonance bandwidth which is typically small. Broadband electric field enhancement over a large wavelength range (~ 2-10 μm) in the mid-infrared (Phys. Rev. Lett. 107, 163902(2011)) is possible using a double-grooved metallic structure as it operates non-resonantly. We will describe recent developments in the fabrication and optical response of broadband electric field enhancement structure.