Microwave dynamics of high aspect ratio superconducting nanowires studied using self-resonance

Journal Article · Tue Jun 21 04:00:00 EDT 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4954068· OSTI ID:22596812

Adams, Jesse K.; Grant, Lierd E. ^[1]; McCaughan, Adam N.; Berggren, Karl K. ^[2]

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1. Department of Physics, University of North Florida, Jacksonville, Florida 32224 (United States)
2. Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

We study the microwave impedance of extremely high aspect ratio (length/width ≈ 5000) superconducting niobium nitride nanowires. The nanowires are fabricated in a compact meander geometry that is in series with the center conductor of a 50 Ω coplanar waveguide transmission line. The transmission coefficient of the sample is measured up to 20 GHz. At high frequency, a peak in the transmission coefficient is seen. Numerical simulations show that this is a half-wave resonance along the length of the nanowire, where the nanowire acts as a high impedance, slow wave transmission line. This resonance sets the upper frequency limit for these nanowires as inductive elements. Fitting simulations to the measured resonance enables a precise determination of the nanowire's complex sheet impedance at the resonance frequency. The real part is a measure of dissipation, while the imaginary part is dominated by kinetic inductance. We characterize the dependence of the sheet resistance and sheet inductance on both temperature and current and compare the results to recent theoretical predictions for disordered superconductors. These results can aid in the understanding of high frequency devices based on superconducting nanowires. They may also lead to the development of novel superconducting devices such as ultra-compact resonators and slow-wave structures.

• OSTI ID: 22596812
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 23 Vol. 119; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ASPECT RATIO
COMPARATIVE EVALUATIONS
COMPUTERIZED SIMULATION
GHZ RANGE 01-100
IMPEDANCE
INDUCTANCE
LENGTH
MICROWAVE RADIATION
NANOWIRES
NIOBIUM NITRIDES
RESONANCE
RESONATORS
SUPERCONDUCTING DEVICES
SUPERCONDUCTORS
WAVEGUIDES