  In metal nanostructures under illumination, multiple different processes can
drive current flow, and in an open- circuit configuration some of these
processes lead to the production of open-circuit photovoltages. Structures that
have plasmonic resonances at the illumination wavelength can have enhanced
photovoltage response, due to both increased interactions with the incident
radiation field, and processes made possible through the dynamics of the
plasmon excitations themselves. Here we review photovoltage response driven by
thermoelectric effects in continuous metal nanowires and photovoltage response
driven by hot electron production and tunneling. We discuss the prospects for
enhancing and quantifying hot electron generation and response via the
combination of local plasmonic resonances and propagating surface plasmon
polaritons.
