Low-loss single crystal silver thin films for nanoplasmonics and metamaterials

Abstract

We present a simple and robust crystal growth technique, which yields large area single crystal films of silver ideally suited for fabricating plasmonic devices and high-finesse metamaterials. The low-loss silver films with thickness of 110 nm were grown on mica substrates at 500 °C by using a sputtering method. We confirmed high quality of the silver thin films by measuring surface roughness and optical constants. The quality factor of the surface plasmon polaritons estimated from the measured optical constants is 6000 at the wavelength of 1 µm, which is about 20 times higher than the single crystal gold thin films epitaxially grown on LiF substrates.