Propagation of Visible Light in Nanostructured Niobium Stripes Embedded in a Dielectric Polymer

TL;DR

This paper demonstrates the propagation of visible light in nanostructured niobium stripes embedded in a dielectric polymer, using surface plasmon polaritons, highlighting potential for unique nano-photonic functionalities despite lossy propagation.

Contribution

It introduces niobium as a viable alternative to noble metals for plasmonic light transport in nanostructures, with experimental evidence of surface plasmon polariton propagation.

Findings

Surface plasmon polaritons are generated at the Nb/polymer interface.

Light propagation is demonstrated via Raman signal of black phosphorus.

Propagation length is limited by niobium's lossy optical properties.

Abstract

Nanometric metallic stripes allow the transmission of optical signals via the excitation and propagation of surface-localized evanescent electromagnetic waves, with important applications in the field of nano-photonics. Whereas this kind of plasmonic phenomena typically exploits noble metals, like Ag or Au, other materials can exhibit viable light-transport efficiency. In this work, we demonstrate the transport of visible light in nanometric niobium stripes coupled with a dielectric polymeric layer, exploiting the remotely-excited/detected Raman signal of black phosphorus (bP) as the probe. The light-transport mechanism is ascribed to the generation of surface plasmon polaritons at the Nb/polymer interface. The propagation length is limited due to the lossy nature of niobium in the optical range, but this material may allow the exploitation of specific functionalities that are absent in noble-metal counterparts.