Evidence for Electromagnetic Granularity in the Polycrystalline Iron-Based Superconductor LaO(0.89)F(0.11)FeAs

Abstract

The new rare-earth arsenate superconductors are layered, low carrier density compounds with many similarities to the high-Tc cuprates. An important question is whether they also exhibit weak coupling across randomly oriented grain-boundaries. In this work we show considerable evidence for such weak-coupling by study of the dependence of magnetization in bulk and powdered samples. Bulk sample magnetization curves show very little hysteresis while remnant magnetization shows almost no sample size dependence, even after powdering. We conclude that these samples exhibit substantial electromagnetic granularity on a scale approximating the grain size, though we cannot yet determine whether this is intrinsic or extrinsic.

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 2008
Accession Number
ADA524169

Entities

People

  • A. A. Polyanskii
  • A. Yamamoto*
  • C. Tarantini
  • D. C. Larbalestier
  • E. E. Hellstrom
  • F. Kametani
  • Frank Hunte
  • J. Jaroszyński
  • Jiahua Jiang
  • N. Craig

Organizations

  • National High Magnetic Field Laboratory

Tags

Communities of Interest

  • Air Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Boundaries
  • Ceramic Materials
  • Electron Microscopes
  • Electron Microscopy
  • Grain Boundaries
  • Grain Size
  • Low Temperature
  • Magnetic Fields
  • Materials
  • Materials Science
  • Microscopes
  • Microscopy
  • Particle Size
  • Polycrystals
  • Scanning Electron Microscopes
  • Scanning Electron Microscopy
  • Superconductors

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
  • Superconducting Magnet Technology