Tunability of Superconducting Metamaterials
Abstract
Metamaterials are artificial structures with unique electromagnetic properties, such as relative dielectric permittivity and magnetic permeability with values less than 1, or even negative. Because these properties are so sensitive to loss, we have developed metamaterials comprised of superconducting waveguides, wires, and split-ring resonators. An important requirement for applications of these metamaterials is the ability to tune the frequency at which the unique electromagnetic response occurs. In this paper we present three methods (unique to superconductors) to accomplish this tuning: temperature, dc magnetic field, and rf magnetic field. Data are shown for dc and rf magnetic field tuning of a single Nb split-ring resonator (SRR). It was found that the dc field tuning was hysteritic in the resonant frequency data, while the quality factor, , was less hystertic. The rf power tuning showed no hysteresis, but did show supression of the at high power. Magneto-optical images reveal inhomogeneous magnetic vortex entry in the dc field tuning, and laser scanning photoresponse images for a YBaCuO SRR reveals the current distribution in the rings.
Cite
@article{arxiv.cond-mat/0608737,
title = {Tunability of Superconducting Metamaterials},
author = {Michael C. Ricci and Hua Xu and Ruslan Prozorov and Alexander P. Zhuravel and Alexey V. Ustinov and Steven M. Anlage},
journal= {arXiv preprint arXiv:cond-mat/0608737},
year = {2009}
}
Comments
RexTEX, 4 pages of text with 6 figures plus 1/5 page of references, submitted for the 2006 Applied Superconductivity Conference; Revised edition: spelling corrections, and we removed mention of measuring the Current Density and replaced this with a more explicit definition of what we measure (with reference)