Quantum and nonlocal phenomena in plasmonic nanoparticles

The field of plasmonics is widely explored with a classical mindset, while recent experimental efforts now reveal plasmon phenomena beyond expectations rooted in classical electrodynamics [1]. In particular, intrinsic length scales of the electron gas are anticipated to manifest in a nonlocal plasmonic response [2] and other quantum corrections to the light-matter interactions [3]. I will discuss theory and experimental efforts to understand nonlocal dynamics (size-dependent frequency shifts and damping) in metallic nanoparticles with true nanoscale dimensions [4], providing also a link between the observed spectral shifts and the fraction of electromagnetic energy attributed to quantum degrees of freedom [5]. \begin{itemize} \item[[1]] S.I. Bozhevolnyi \& N.A. Mortensen, "Plasmonics for emerging quantum technologies", doi:10.1515/nanoph-2016-0179 \item[[2]] S. Raza, S.I. Bozhevolnyi, M. Wubs \& N.A. Mortensen, "Nonlocal optical response in metallic nanostructues", J. Phys. Cond. Matter. {\bf 27}, 183204 (2015) \item[[3]] T. Christensen, W. Yan, A.-P. Jauho, M. Solja{\v c}i{\'c} \& N.A. Mortensen, "Quantum corrections in nanoplasmonics: shape, scale, and material", arXiv:1608.05421 \item[[4]] S. Raza \emph{et al.}, "Multipole plasmons and their disappearance in few-nanometer silver nanoparticles", Nature Communications {\bf 6}, 8788 (2015) \item[[5]] W. Yan \& N.A. Mortensen, "Nonclassical effects in plasmonics: An energy perspective to quantify nonclassical effects", Phys. Rev. B {\bf 93}, 115439 (2016) \end{itemize}