Plasmonic Hot Carrier Photodetection and Energy Conversion

Plasmonic hot carrier photodetection and energy conversion exploit the decay of surface plasmons—collective oscillations of electrons at metal–dielectric interfaces—to generate energetic charge carriers. These hot electrons and holes, produced non-radiatively, can be harvested before thermalisation for applications in photodetectors, photovoltaics, photocatalysis and on-chip sensing. The field integrates nanophotonic design, materials science and quantum transport theory to optimise three key stages: plasmon excitation, hot carrier generation and carrier collection. Advances in nanostructure engineering have yielded devices with narrow spectral selectivity, broadband absorption and dual-polarity carrier extraction. Such developments hold promise for more efficient solar energy converters, ultrasensitive biochemical sensors and ultrafast optical interconnects, with global significance in sustainable energy and information technologies.

Research from Nature Portfolio

Recent studies have elucidated the fundamental mechanisms distinguishing plasmon-induced carriers from those generated by direct photoexcitation. By tuning internal field enhancements and barrier heights in nanowire-based devices, researchers have achieved higher-energy hot-electron collection and improved photocurrent yields. Another line of work has demonstrated broadband plasmonic absorbers based on gold-nanoparticle–TiO₂–gold-film stacks, achieving near-complete visible light absorption and a fivefold increase in incident photon-to-current conversion efficiency across 450–850 nm. Furthermore, investigations of heterogeneous plasmon sources have revealed cooperative interplay between localised and propagating plasmons in a single metal-semiconductor platform, enabling wavelength-controlled polarity-switchable photoconductivity and tunable responsivity across the visible spectrum.

Plasmonic Hot Carrier Photodetection and Energy Conversion publication trend

The graph below shows the total number of articles in plasmonic hot carrier photodetection and energy conversion across all publications each year (not limited to Nature Index journals).

Technical terms

Surface plasmon: collective oscillation of conduction electrons at a metal–dielectric interface.

Hot carrier: a non-equilibrium electron or hole possessing energy significantly above the Fermi level.

Schottky junction: a rectifying metal–semiconductor contact that facilitates carrier injection across a potential barrier.

Localised surface plasmon resonance: confinement of surface plasmons within metallic nanoparticles or nanostructures.

Surface plasmon polariton: a propagating electromagnetic wave bound to a metal–dielectric interface.

Internal photoemission: process by which photoexcited carriers overcome a barrier and are injected into an adjacent material.

Photoconductivity: increase in a material’s electrical conductivity upon absorption of light.

References

1. In situ photoelectric biosensing based on ultranarrowband near-infrared plasmonic hot electron photodetection. Advanced Photonics (2024).
2. Simultaneous Harvesting of Bipolar Plasmonic Hot Carriers for Boosting Photoconductivity in Ag Nanoprism‐Coupled Lateral Si p–n Junction. Advanced Science (2025).
3. Plasmonic hot carrier dynamics in solid-state and chemical systems for energy conversion. Nanophotonics (2016).
4. Harvesting the loss: surface plasmon-based hot electron photodetection. Nanophotonics (2016).
5. Distinguishing between plasmon-induced and photoexcited carriers in a device geometry. Nature Communications (2015).
6. Gap-plasmon based broadband absorbers for enhanced hot-electron and photocurrent generation. Scientific Reports (2016).
7. Interplay of hot electrons from localized and propagating plasmons. Nature Communications (2017).