title: Strong-field plasmonic photoemission in the mid-IR at <1 GW/cm² intensity.
abstract: We investigated nonlinear photoemission from plasmonic films with femtosecond, mid-infrared pulses at 3.1 μm wavelength. Transition between regimes of multi-photon-induced and tunneling emission is demonstrated at an unprecedentedly low intensity of <1 GW/cm(2). Thereby, strong-field nanophysics can be accessed at extremely low intensities by exploiting nanoscale plasmonic field confinement, enhancement and ponderomotive wavelength scaling at the same time. Results agree well with quantum mechanical modelling. Our scheme demonstrates an alternative paradigm and regime in strong-field physics.
authors.affiliation: ICFO-Institut de Ciències Fotòniques, Mediterranean Technology Park, 08860 Castelldefels, Barcelona, Spain.
authors.forename: S M
authors.initials: SM
authors.lastname: Teichmann
authors.affiliation: MTA "Lendület" Ultrafast Nanooptics Group, Wigner Research Centre for Physics, Konkoly-Thege M. út 29-33, 1121 Budapest, Hungary.
authors.forename: P
authors.initials: P
authors.lastname: Rácz
authors.affiliation: Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Str. 1, 85748 Garching, Germany.
authors.forename: M F
authors.initials: MF
authors.lastname: Ciappina
authors.affiliation: Centro de Láseres Pulsados (CLPU), Parque Científico, 37185 Villamayor, Salamanca, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Pérez-Hernández
authors.affiliation: ICFO-Institut de Ciències Fotòniques, Mediterranean Technology Park, 08860 Castelldefels, Barcelona, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Thai
authors.affiliation: MTA "Lendület" Ultrafast Nanooptics Group, Wigner Research Centre for Physics, Konkoly-Thege M. út 29-33, 1121 Budapest, Hungary.
authors.forename: J
authors.initials: J
authors.lastname: Fekete
authors.affiliation: University of Alberta, Department of Electrical and Computer Engineering, T6G 2V4 Edmonton, Alberta, Canada.
authors.forename: A Y
authors.initials: AY
authors.lastname: Elezzabi
authors.affiliation: Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Str. 1, 85748 Garching, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Veisz
authors.affiliation: 1] ICFO-Institut de Ciències Fotòniques, Mediterranean Technology Park, 08860 Castelldefels, Barcelona, Spain [2] ICREA-Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Biegert
authors.affiliation: MTA "Lendület" Ultrafast Nanooptics Group, Wigner Research Centre for Physics, Konkoly-Thege M. út 29-33, 1121 Budapest, Hungary.
authors.forename: P
authors.initials: P
authors.lastname: Dombi