Open AccessFabrication and spectral tuning of standing gold infrared antennas using single fs-laser pulses.
Author(s) -
Martin Reininghaus,
Dirk Wortmann,
Zhao Cao,
Jón Mattis Hoffmann,
Thomas Taubner
Publication year - 2013
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.21.032176
Subject(s) - optics , materials science , laser , optoelectronics , antenna (radio) , resonance (particle physics) , plasmon , wavelength , physics , telecommunications , particle physics , computer science
Upright standing gold monopole nanoantennas are fabricated by irradiation of thin gold films with single pulses of fs-laser radiation. The resulting antennas exhibit extinction resonances in the mid infrared spectral rage for p-polarized light under grazing incidence. Due to the free charge carriers in the surrounding gold film of the antenna, the resonance condition of the thin-wire monopole antenna can be explained by introducing image charges yielding an observable resonance wavelength of four times the antenna length. The antenna length is controlled coarsely by the focusing numerical aperture and fine by the pulse energy of the laser pulse producing the structure. An additional ultrafine tuning of the resonance wavelength with a sub-10 nm resolution is realized by an additional coating process subsequent to the laser structuring.