Authors: L.Y.M.A. Tobing; D. Zhang; K.S. Low; D-H. Zhang
Addresses: School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore ' Shanghai Key Laboratory of Modern Optics System, School of Optics-Electrical and Computer Engineering, University of Shanghai for Science and Technology, 516 Jungong Road, 200093, Shanghai, China ' School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore ' School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
Abstract: We present fabrication and optical properties of sub-wavelength metallic structures, including the sub-100 nm size gold and silver split ring resonators (SRRs). It is shown that introducing rotational symmetry into SRR array could enhance the resonance magnitude of magnetic and electric modes under unpolarised light illumination, thus enabling SRR optical characterisation using simple unpolarised light. Sub-100-nm SRRs will be shown to have magnetic resonance entering in the visible frequency range, where silver SRR as small as ~60 nm had been successfully fabricated with fundamental magnetic resonance at ~604 nm. The resonance wavelengths of the LC and plasmon modes of the sub-100-nm SRRs are found to linearly decrease with the decrease of SRR size, suggesting that kinetic inductance has not yet occurred at such frequency and also the possibility of having shorter magnetic resonance wavelength.
Keywords: metamaterials; split ring resonators; SRR arrays; plasmonics; e-beam lithography; gold resonators; silver resonators; optical properties; nanotechnology; rotational symmetry; resonance magnitude; magnetic resonance; kinetic inductance.
International Journal of Nanotechnology, 2016 Vol.13 No.7, pp.561 - 570
Published online: 17 Aug 2016 *Full-text access for editors Access for subscribers Purchase this article Comment on this article