Projects per year
In this article we experimentally and theoretically study the plasmonic properties of discrete copper nanocups fabricated by magnetron sputtering on ordered, non-close-packed colloidal templates. Wide tunability of the main plasmon resonance peak between 900 and 1500 nm, extending the typical plasmon resonance range previously reported for other copper nanostructures between 600 and 1000 nm, is achieved by varying shell thickness and particle size in the colloidal template. The nature of the plasmon resonance peaks is revealed from calculated charge maps and electromagnetic field intensity maps. Good agreements are found between experimental and calculated extinction spectra, which validates the geometry model and suggests that the nanocups have a well-defined shape. The main plasmon resonance peak exhibits a minor red-shift and attenuation after 3 days of oxidation and eventually stabilizes after 13 days. We also demonstrate that a potentially useful optical material that blocks near-infrared but transmits visible light can be constructed by mixing copper nanocups of three different sizes at appropriate ratios.
Bibliographical noteFunding Information:
This work was a part of the Multidisciplinary University Research Initiative (MURI) Program Grant. It was primarily supported by the Army Office of Research under MURI Grant W911NF-12-1-0407. X.-T.K. was also supported by China Postdoctoral Science Foundation (2015M580778) and the Volkswagen Foundation. A.O.G. was also supported via Changjiang Chair Professorship (China) and the Volkswagen Foundation. Parts of this work were carried out in the Characterization Facility, University of Minnesota, a member of the NSF-funded Materials Research Facilities via the MRSEC program.
- template-assisted magnetron sputtering
How much support was provided by MRSEC?
Reporting period for MRSEC
- Period 4