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Au-Ag-Cu nano-alloys: tailoring of permittivity.

ABSTRACT: Precious metal alloys enables new possibilities to tailor materials for specific optical functions. Here we present a systematic study of the effects of a nanoscale alloying on the permittivity of Au-Ag-Cu metals at 38 different atomic mixing ratios. The permittivity was measured and analyzed numerically by applying the Drude model. X-ray diffraction (XRD) revealed the face centered cubic lattice of the alloys. Both, optical spectra and XRD results point towards an equivalent composition-dependent electron scattering behavior. Correlation between the fundamental structural parameters of alloys and the resulting optical properties is elucidated. Plasmonic properties of the Au-Ag-Cu alloy nanoparticles were investigated by numerical simulations. Guidelines for designing plasmonic response of nano- structures and their patterns are presented from the material science perspective.

SUBMITTER: Hashimoto Y

PROVIDER: S-EPMC4846990 | biostudies-literature |

REPOSITORIES: biostudies-literature

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High optical enhancement in Au/Ag alloys and porous Au using Surface-Enhanced Raman spectroscopy technique.

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