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arXiv · 1912.00460

Generation of plasmonic hot carriers from d-bands in metallic nanoparticles

Lara Román Castellanos·Juhan Matthias Kahk·Ortwin Hess·Johannes Lischner
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Abstract

We present an approach to master the well-known challenge of calculating the contribution of d-bands to plasmon-induced hot carrier rates in metallic nanoparticles. We generalise the widely used spherical well model for the nanoparticle wavefunctions to flat d-bands using the envelope function technique. Using Fermi's golden rule, we calculate the generation rates of hot carriers after the decay of the plasmon due to transitions from either a d-band state to an sp-band state or from an sp-band state to another sp-band state. We apply this formalism to spherical silver nanoparticles with radii up to 20~nm and also study the dependence of hot carrier rates on the energy of the d-bands. We find that for nanoparticles with a radius less than 2.5~nm sp-band state to sp-band state transitions dominate hot carrier production while d-band state to sp-band state transitions give the largest contribution for larger nanoparticles.

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Lara Román Castellanos, Juhan Matthias Kahk, Ortwin Hess, Johannes Lischner. 2020-02-13. Generation of plasmonic hot carriers from d-bands in metallic nanoparticles. https://doi.org/10.1063/5.0003123

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