Nonlinear Plasmonic Photoelectron Response of Ag(111)

Marcel Reutzel, Andi Li, Branko Gumhalter, and Hrvoje Petek

Phys. Rev. Lett. 123, 017404 – Published 3 July 2019

Abstract

Photons can excite collective and single-particle excitations in metals; the collective plasmonic excitations are of keen interest in physics, chemistry, optics, and nanotechnology because they enhance coupling of electromagnetic energy and can drive nonlinear processes in electronic materials, particularly where their dielectric function $ϵ (ω)$ approaches zero. We investigate the nonlinear angle-resolved two-photon photoemission (2PP) spectroscopy of the Ag(111) surface through the $ϵ (ω)$ near-zero region. In addition to the Einsteinian single-particle photoemission, the 2PP spectra report unequivocal signatures of nonlocal dielectric, plasmonically enhanced, excitation processes.

Received 4 September 2018

DOI:https://doi.org/10.1103/PhysRevLett.123.017404

Physics Subject Headings (PhySH)

Dielectric properties Photoemission Surface plasmons Surface states

Metals

Ellipsometry Optical absorption spectroscopy Two-photon photoelectron spectroscopy

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Marcel Reutzel^1,*, Andi Li¹, Branko Gumhalter², and Hrvoje Petek ^1,†

¹Department of Physics and Astronomy and Pittsburgh Quantum Institute, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
²Institute of Physics, HR-10000 Zagreb, Croatia