Synthesis and Plasmonics of Surface-Truncated Noble Metal Nanostructures for Advanced Nanoantenna Engineering

The increasing interest in on-chip plasmonic devices underscores the importance of having a fundamental understanding of the interactions occurring when noble metal nanostructures are brought into contact with substrate materials. The resulting adjustments to the plasmon resonances and electric near-fields are both significant and unavoidable. In the solid-state dewetting of ultrathin metal films specifically, an important nanosynthesis technique for many modern technologies, the resulting spherical nanostructures exhibit a thermodynamically determined truncation by the substrate. The effects of introducing asymmetry in both the surface structure and the dielectric environment are critical for determining optoelectronic properties and are hence impactful parameters to understand and manipulate in the rational design of on-chip plasmonic devices. Herein, is demonstrated a comprehensive study of the effects of surface truncation on the plasmon resonance and near-fields of substrate-truncated nanostructures, beginning with Ag nanospheres, and expanding to include Au nanostars and hexagonal Au nanoplates.