Single plasmon hot carrier generation in metallic nanoparticles

• Published in: Communications physics 2019-05, Vol.2 (1), Article 47
• Main Authors: Román Castellanos, Lara, Hess, Ortwin, Lischner, Johannes
• Format: Article
• Language: English
• Subjects: 639/301/119/995; 639/4077/909; 639/638/440; 639/638/563/758; 639/638/563/979; Decay; Excitation; Hot electrons; Nanoparticles; Optoelectronics; Physics; Physics and Astronomy; Plasmonics; Plasmons
• ISSN: 2399-3650; 2399-3650
• DOI: 10.1038/s42005-019-0148-2

Hot carriers produced from the decay of localized surface plasmons in metallic nanoparticles are intensely studied because of their optoelectronic, photovoltaic and photocatalytic applications. From a classical perspective, plasmons are coherent oscillations of the electrons in the nanoparticle, but their quantized nature comes to the fore in the novel field of quantum plasmonics. In this work, we introduce a quantum-mechanical material-specific approach for describing the decay of single quantized plasmons into hot electrons and holes. We find that hot carrier generation rates differ significantly from semiclassical predictions. We also investigate the decay of excitations without plasmonic character and show that their hot carrier rates are comparable to those from the decay of plasmonic excitations for small nanoparticles. Our study provides a rigorous and general foundation for further development of plasmonic hot carrier studies in the plasmonic regime required for the design of ultrasmall devices. Hot carrier generation via plasmon decay is an important mechanism in quantum plasmonics and is typically understood using semiclassical theory however a fully quantum method is required to properly analyse such systems. To this end, the authors develop a quantum-mechanical approach to describe the decay of quantized plasmons into hot electrons and holes.