Toward Next Generation Plasmonic Nanopore Slit Platform with a ~10 nm Slit-Width

Abstract

We fabricated various nanoaperture plasmonic platforms for single-molecule detection. We fabricated nanoapertures like nanopores on a pyramid and nanoslits on an Au flat membrane using a Ga ion focused ion beam drilling technique, followed by irradiating with a high energy electron beam, dependent on the electron beam current density to obtain nanoapertures with a few nanometer sizes (circular nanopore, nanoslit pores). We examined their optical characteristics with varying aperture sizes and sample thicknesses. We obtained broad emission spectra in the visible and infrared region from the (7 x 7) slit array and a sharp, strong infrared emission peak from the Au nanoparticle on the substrate. The fabricated Au platform with ~10 nm nanometer opening can be employed as a single-molecule sensor and an infrared thermal emission device.