1999/10/31 by Orjan Festin, Örjan Festin, Peter Svedlindh +6
Engineering · Physics and Astronomy · #Characterization and Applications of Magnetic Nanoparticles #Physics of Superconductivity and Magnetism #Theoretical and Computational Physics #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevlett.83.5567
published as Phys. Rev. Lett. 83, 5567 (1999). · 5 pages including 4 figures in two columns, to appear in Phys. Rev. Lett
arxiv created 1999/11/01 · openalex publication_date 1999/12/27 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The flux noise spectrum and complex impedance for a 500 \AA thick YBCO film are measured and compared with predictions for two-dimensional vortex fluctuations. It is verified that the complex impedance and the flux noise spectra are proportional to each other, that the logarithm of the flux noise spectra for different temperatures has a common tangent with slope \ensuremath≈\ensuremath-1, and that the amplitude of the noise decreases as d^\ensuremath-3, where d is the height above the film at which the magnetic flux is measured. A crossover from normal to anomalous vortex diffusion is indicated by the measurements and is discussed in terms of a two-dimensional decoupling.