Near-Field Plasmonic Behavior of Au/Pd Nanocrystals with Pd-Rich Tips

Emilie Ringe; Christopher J. DeSantis; Sean M. Collins; Martial Duchamp; Rafal E. Dunin-Borkowski; Sara E. Skrabalak; Paul A. Midgley

arXiv · 1506.01650

Near-Field Plasmonic Behavior of Au/Pd Nanocrystals with Pd-Rich Tips

Emilie Ringe·Christopher J. DeSantis·Sean M. Collins·Martial Duchamp·Rafal E. Dunin-Borkowski·Sara E. Skrabalak·Paul A. Midgley

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Abstract

Using nanometer spatial resolution electron-energy loss spectroscopy (EELS), energy dispersive X-ray spectroscopy (EDS), and cathodoluminescence (CL) mapping, we demonstrate that Au alloys containing a poor plasmonic metal (Pd) can nevertheless sustain multiple size-dependent localized surface plasmon resonances and observe strong field enhancement at Pd-rich tips, where the composition is in fact least favorable for plasmons. These Au/Pd stellated nanocrystals are also involved in substrate and interparticle coupling, as unraveled by EELS tilt series.

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Emilie Ringe, Christopher J. DeSantis, Sean M. Collins, Martial Duchamp, Rafal E. Dunin-Borkowski, Sara E. Skrabalak, Paul A. Midgley. 2015-06-04. Near-Field Plasmonic Behavior of Au/Pd Nanocrystals with Pd-Rich Tips. https://arxiv.org/abs/1506.01650

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