title: Giant electric field enhancement in split ring resonators featuring nanometer-sized gaps.
abstract: Today's pulsed THz sources enable us to excite, probe, and coherently control the vibrational or rotational dynamics of organic and inorganic materials on ultrafast time scales. Driven by standard laser sources THz electric field strengths of up to several MVm(-1) have been reported and in order to reach even higher electric field strengths the use of dedicated electric field enhancement structures has been proposed. Here, we demonstrate resonant electric field enhancement structures, which concentrate the incident electric field in sub-diffraction size volumes and show an electric field enhancement as high as ~14,000 at 50 GHz. These values have been confirmed through a combination of near-field imaging experiments and electromagnetic simulations.
authors.affiliation: 1] Laboratory of Micro- and Nanotechnology Paul Scherrer Institute, Villigen 5232, Switzerland [2] Institute of Applied Physics University of Bern, Bern 3012, Sidlerstrasse 5, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Bagiante
authors.affiliation: 1] Laboratory of Micro- and Nanotechnology Paul Scherrer Institute, Villigen 5232, Switzerland [2] Institute of Applied Physics University of Bern, Bern 3012, Sidlerstrasse 5, Switzerland.
authors.forename: F
authors.initials: F
authors.lastname: Enderli
authors.affiliation: Institute of Applied Physics University of Bern, Bern 3012, Sidlerstrasse 5, Switzerland.
authors.forename: J
authors.initials: J
authors.lastname: Fabiańska
authors.affiliation: Laboratory of Micro- and Nanotechnology Paul Scherrer Institute, Villigen 5232, Switzerland.
authors.forename: H
authors.initials: H
authors.lastname: Sigg
authors.affiliation: Institute of Applied Physics University of Bern, Bern 3012, Sidlerstrasse 5, Switzerland.
authors.forename: T
authors.initials: T
authors.lastname: Feurer