APS March Meeting 2016
Volume 61, Number 2
Monday–Friday, March 14–18, 2016;
Baltimore, Maryland
Session A23: Novel Plasmonic Effects and Devices
8:00 AM–11:00 AM,
Monday, March 14, 2016
Room: 322
Sponsoring
Unit:
DMP
Chair: Natalia Litchinitser, State University of New York, Buffalo
Abstract ID: BAPS.2016.MAR.A23.1
Abstract: A23.00001 : Plasmonic Nanomaterials for Optical-to-Electrical Energy Conversion
8:00 AM–8:36 AM
Preview Abstract
Abstract
Author:
Matthew Sheldon
(Texas A&M University)
High-quality semiconductor solids have been the dominant photovoltaic
materials platform for decades. Although several alternative approaches have
been proposed, e.g. dye-sensitized cells or polymeric solids, none compete
in terms of cost and conversion efficiency, the crucial benchmarks for
industrial scale implementation. However, semiconductors suffer from several
fundamental limitations relating to the microscopic mechanism of power
conversion that preclude them, even theoretically, from achieving conversion
efficiency at the Carnot limit of 95{\%}. Indeed, the fundamentally
different tasks of semiconductors in photovoltaic devices, both as optical
absorbers, and separately, for electron-hole pair separation and collection,
often demand opposing trade-offs in materials optimization.
Alternatively, recent advances in subwavelength metal optics, e.g.
nanophotonics, metamaterials, and plasmonics, provide several new examples
where nanostructured metals perform the separate tasks of absorption and
charge separation necessary for photovoltaic power conversion.
Nanostructured metals are extremely efficient broadband absorbers of
radiation, with tailorable optical properties throughout the visible and
infrared spectrum. It is traditionally assumed that the lack of a band gap
and consequent fast electronic relaxation (fs) and short mean free path (
100 nm) hinders efficient carrier collection. However, new phenomena
resulting from the remarkable energy concentration and nanoscale collection
geometry afforded by plasmonic systems suggest new strategies may be
possible that use all metal structures. In this talk, I will describe two
ongoing studies in our laboratory that exemplify opportunities for
metal-based optical energy conversion: (1) Excitation with circularly
polarized illumination can induce strong, persistent electrical drift
currents in resonant metal nanostructures via the inverse faraday effect.
(2) Plasmonic absorption in metal nanostructures provides an entirely new
mechanism for generating electrochemical potential from photons. This
behavior is termed a `plasmoelectric effect' (\textit{Science, 2014}).
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2016.MAR.A23.1