Weak localization and magnetoconductance in percolative superconducting aluminum films

Kazumasa Yamada, Bunjyu Shinozaki, Takashi Kawaguti

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

In order to investigate the crossover from a homogeneous behavior to an inhomogeneous (percolative) one, the temperature T and magnetic field H dependence of the sheet resistance R have been measured for two-dimensional granular aluminum films. Fitting the theory to data on magnetoconductance near TC with use of the diffusion constant D(T) as a fitting parameter, we have obtained the anomalous T-dependent diffusion constant D. From D(T), the electron diffusion index θ, a certain critical exponent in the percolation theory, has been obtained. In the relation R -θ, the value of θ varies abruptly near 1.5 kΩ. This behavior suggests the abovementioned crossover is similar to our previous results determined from the T dependence of the upper critical magnetic field. For percolative films at H=5 T, we have found the strong R dependence of the prefactor αT in the expression σ=[αTe2/(2π2ℏ) ]ln T+σ0. The relation αT∝1/R can be explained qualitatively by a model of scaling law for percolation.

Original languageEnglish
Article number144503
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume70
Issue number14
DOIs
Publication statusPublished - Oct 1 2004

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Aluminum
aluminum
crossovers
Magnetic fields
electron diffusion
Scaling laws
Sheet resistance
magnetic fields
scaling laws
exponents
Electrons
Temperature
temperature

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Weak localization and magnetoconductance in percolative superconducting aluminum films. / Yamada, Kazumasa; Shinozaki, Bunjyu; Kawaguti, Takashi.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 70, No. 14, 144503, 01.10.2004.

Research output: Contribution to journalArticle

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