title: Mid-infrared plasmonic inductors: enhancing inductance with meandering lines.
abstract: We present a mid-infrared inductor that when applied to an extraordinary transmission hole array produces a strong redshift of the resonant peak accompanied by an unprecedented enlargement of the operation bandwidth. The importance of the result is twofold: from a fundamental viewpoint, the direct applicability of equivalent circuit concepts borrowed from microwaves is demonstrated, in frequencies as high as 17 THz upholding unification of plasmonics and microwave concepts and allowing for a simplification of structure design and analysis; in practical terms, a broadband funnelling of infrared radiation with fractional bandwidth and efficiency as high as 97% and 48%, respectively, is achieved through an area less than one hundredth the squared wavelength, which leads to an impressive accessible strong field localization that may be of great interest in sensing applications.
authors.affiliation: TERALAB (MmW - THz - IR & Plasmonics Laboratory), Universidad Pública de Navarra, 31006, Pamplona, Spain.
authors.forename: Víctor
authors.initials: V
authors.lastname: Torres
authors.affiliation: TERALAB (MmW - THz - IR & Plasmonics Laboratory), Universidad Pública de Navarra, 31006, Pamplona, Spain.
authors.forename: Rubén
authors.initials: R
authors.lastname: Ortuño
authors.affiliation: TERALAB (MmW - THz - IR & Plasmonics Laboratory), Universidad Pública de Navarra, 31006, Pamplona, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Rodríguez-Ulibarri
authors.affiliation: Nanophotonics Technology Center, Universitat Politècnica de València, 46022, Valencia, Spain.
authors.forename: Amadeu
authors.initials: A
authors.lastname: Griol
authors.affiliation: Nanophotonics Technology Center, Universitat Politècnica de València, 46022, Valencia, Spain.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Martínez
authors.affiliation: Optical and Semiconductor Devices Group, Department of Electrical and Electronic Engineering, Imperial College London, SW7 2BT, London, UK.
authors.forename: Miguel
authors.initials: M
authors.lastname: Navarro-Cía
authors.affiliation: TERALAB (MmW - THz - IR & Plasmonics Laboratory), Universidad Pública de Navarra, 31006, Pamplona, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Beruete
authors.affiliation: TERALAB (MmW - THz - IR & Plasmonics Laboratory), Universidad Pública de Navarra, 31006, Pamplona, Spain.
authors.forename: Mario
authors.initials: M
authors.lastname: Sorolla