Photovoltages and hot electrons in plasmonic nanogaps

TL;DR

This paper reviews how plasmonic nanostructures generate photovoltages through thermoelectric effects and hot electron dynamics, highlighting the potential for enhanced photoresponse via surface plasmon polaritons.

Contribution

It provides a comprehensive review of photovoltage mechanisms in plasmonic nanogaps, emphasizing hot electron generation and the role of surface plasmon polaritons.

Findings

Enhanced photovoltage response due to plasmonic resonances.

Hot electron production and tunneling contribute to photocurrent.

Potential for improved photodetectors using plasmonic effects.

Abstract

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.