Eutectic Liquid Alloys for Plasmonics: Theory and Experiment

Abstract

We report a method based on density functional theory molecular dynamics that allows us to calculate the plasmonic properties of liquid metals and metal alloys from first principles with no a priori knowledge of the system. We show exceptional agreement between the simulated and measured optical constants of liquid Ga and the room temperature liquid In-Ga eutectic alloy (T(m) = 289 K). We then use this method to analyze the plasmonic properties of various alloy concentrations in the In-Ga system. The plasmonic performance of the In-Ga system decreases with increasing In concentration. However, the benefits of a room-temperature plasmonic liquid are likely to outweigh the minor reduction in plasmonic performance when moving from pure Ga to the eutectic composition. Our results show that density functional theory molecular dynamics can be used as a predictive tool for studying the optical properties of liquid metal systems amenable to plasmonics.

Plasmonics in the Ultraviolet with Aluminum, Gallium, Magnesium and Rhodium

“…The liquid phase showed higher surface plasmon polaritons coupling efficiencies and narrower resonance line widths compared to the solid phase. In order to predict the optical constants of liquid metals and metal alloys, Blaber et al [68] proposed a density functional theory molecular dynamics model that allows to calculate them from first principles with no a priori knowledge of the system. This method was tested on liquid Ga and In-Ga eutectic alloy.…”

How an oxide shell affects the ultraviolet plasmonic behavior of Ga, Mg, and Al nanostructures

“…Consequently, both humidity and Joule heating can produce efficiency losses in both metals and blue-shifts of the resonances in Al after several uses. Although gallium shows the weakest resonance and strongest oxide sensitivity, it is of interest because its oxide is thin and stable, its resonances in the UV [11,12] are broad, and its low melting point makes it suitable for eutectic alloys that may improve its plasmonic performance [37].…”

Tunneling-induced broadband and tunable optical emission from plasmonic nanorod metamaterials

“…Tabulated values were taken for optical properties of gold [28], with an additional mean free path correction of 3 nm [29], representing the granulated nature of the electrodeposited gold, which was determined to be appropriate in previous studies [30]. The optical properties of EGaIn, SiO 2 , and Al 2 O 3 were approximated by the Drude model (with high-frequency optical constant ε ∞ = 1.08, plasma frequency ω p = 13.5 eV, and scattering rate γ = 1.05 eV) [31] and Sellmeier models [32,33], respectively, while tabulated data were taken for T 2 O 5 [34].…”