title: Quantum mechanical effects in plasmonic structures with subnanometre gaps.
abstract: Metallic structures with nanogap features have proven highly effective as building blocks for plasmonic systems, as they can provide a wide tuning range of operating frequencies and large near-field enhancements. Recent work has shown that quantum mechanical effects such as electron tunnelling and nonlocal screening become important as the gap distances approach the subnanometre length-scale. Such quantum effects challenge the classical picture of nanogap plasmons and have stimulated a number of theoretical and experimental studies. This review outlines the findings of many groups into quantum mechanical effects in nanogap plasmons, and discusses outstanding challenges and future directions.
authors.affiliation: Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.|Maryland Nano-Center, University of Maryland, College Park, Maryland 20742, USA.
authors.forename: Wenqi
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Material Physics Center CSIC-UPV/EHU and Donostia International Physics Center DIPC, Paseo Manuel de Lardizabal 5, Donostia-San Sebastián 20018, Spain.
authors.forename: Ruben
authors.initials: R
authors.lastname: Esteban
authors.affiliation: Material Physics Center CSIC-UPV/EHU and Donostia International Physics Center DIPC, Paseo Manuel de Lardizabal 5, Donostia-San Sebastián 20018, Spain.|Institut des Sciences Moléculaires d'Orsay - UMR 8214, CNRS-Université Paris Sud, Bâtiment 351, Orsay 91405, France.
authors.forename: Andrei G
authors.initials: AG
authors.lastname: Borisov
authors.affiliation: Nanophotonics Centre, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK.
authors.forename: Jeremy J
authors.identifier: 0000-0002-9606-9488
authors.initials: JJ
authors.lastname: Baumberg
authors.affiliation: Department of Physics, MS61, Laboratory for Nanophotonics, Rice University, Houston, Texas 77005, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Nordlander
authors.affiliation: Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
authors.forename: Henri J
authors.initials: HJ
authors.lastname: Lezec
authors.affiliation: Material Physics Center CSIC-UPV/EHU and Donostia International Physics Center DIPC, Paseo Manuel de Lardizabal 5, Donostia-San Sebastián 20018, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Aizpurua
authors.affiliation: School of Physics, University of Melbourne, Victoria 3010, Australia.|Department of Electrical and Electronic Engineering, University of Melbourne, Victoria 3010, Australia.
authors.forename: Kenneth B
authors.initials: KB
authors.lastname: Crozier