title: Hot Carrier Extraction with Plasmonic Broadband Absorbers.
abstract: Hot charge carrier extraction from metallic nanostructures is a very promising approach for applications in photocatalysis, photovoltaics, and photodetection. One limitation is that many metallic nanostructures support a single plasmon resonance thus restricting the light-to-charge-carrier activity to a spectral band. Here we demonstrate that a monolayer of plasmonic nanoparticles can be assembled on a multistack layered configuration to achieve broadband, near-unit light absorption, which is spatially localized on the nanoparticle layer. We show that this enhanced light absorbance leads to ∼40-fold increases in the photon-to-electron conversion efficiency by the plasmonic nanostructures. We developed a model that successfully captures the essential physics of the plasmonic hot electron charge generation and separation in these structures. This model also allowed us to establish that efficient hot carrier extraction is limited to spectral regions where (i) the photons have energies higher than the Schottky junctions and (ii) the absorption of light is localized on the metal nanoparticles.
authors.affiliation: Manufacturing, CSIRO , Private Bag 33, Clayton, Victoria 3168, Australia.|Australian National Fabrication Facility, Melbourne Centre for Nanofabrication , Clayton Victoria 3168, Australia.
authors.forename: Charlene
authors.initials: C
authors.lastname: Ng
authors.forename: Jasper J
authors.initials: JJ
authors.lastname: Cadusch
authors.affiliation: Manufacturing, CSIRO , PO Box 218, Lindfield New South Wales 2070, Australia.
authors.forename: Svetlana
authors.initials: S
authors.lastname: Dligatch
authors.forename: Ann
authors.initials: A
authors.lastname: Roberts
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Davis
authors.forename: Paul
authors.initials: P
authors.lastname: Mulvaney
authors.affiliation: Manufacturing, CSIRO , Private Bag 33, Clayton, Victoria 3168, Australia.|Australian National Fabrication Facility, Melbourne Centre for Nanofabrication , Clayton Victoria 3168, Australia.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Gómez
keywords: hot spots; near fields; photocatalysis; surface enhancements; surface plasmons