Alloy dielectric functions for nanoplasmonics

Metallic nanoparticles can support strong localized surface plasmon resonances (LSPRs), which underpin various applications in sensing and energy conversion. LSPRs are tunable by composition, which affects the dielectric response, as well as geometry. While the role of the latter has been explored extensively, the utilization of the compositional degrees of freedom is lagging by comparison.

To accelerate the development of rationally designed metal alloy systems for nanophotonic applications and to thereby unlock the potential of alloying for tailoring nanostructure optical properties, one requires accurate complex dielectric functions. To date, however, accurate alloy dielectric functions are widely lacking. We just published a paper in Advanced Functional Materials, in which we present a comprehensive binary alloy dielectric function library for the late transition metals most commonly employed in plasmonics (Ag, Au, Cu, Pd, Pt).

At the same time we published a web application that serves as a particular convenient platform to access these data. We thereby expect this library to become a key resource for the development of alloy nanomaterials for applications in nanophotonics, optical sensors, and photocatalysis.