Published January 1, 1995 | Version v1
Journal article

Surface barrier in Hg-based polycrystalline superconductors

  • 1. National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306-4005 (United States)
  • 2. Department of Physics, The University of Tennessee, Knoxville, Tennessee 37996-1200 (United States)
  • 3. Solid State Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6061 (United States)
  • 4. Department of Mechanical Engineering, Florida A ampersand M University, Tallahassee, Florida 32308 (United States)
  • 5. National High Magnetic Field Laboratory and College of Engineering, Florida State University, Tallahassee, Florida 32306-4005 (United States)
  • 6. Chemical and Analytical Sciences Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6100 (United States)

Description

Pronounced effects of a surface barrier are frequently observed on polycrystalline superconductors of HgBa2Can-1CunO2n+2+Δ [Hg-12(n-1)n] with n=1, 2, and 3. Compared with other known high-temperature superconductors, the effects at low temperatures are much stronger and persist over a wide range of magnetic fields. The present analysis shows that the enhancement of the irreversible magnetization of grains by the surface barrier is comparable to that by neutron irradiations. The magnitude of the surface supercurrent density is >4x107 A/cm2 at T=40 K and H=45 kG, for Hg-1223. The upper and lower boundaries of the thickness of the vortex-free region and the surface-current density are analyzed as functions of temperature and field

Additional details

Publishing Information

Journal Title
Physical Review. B, Condensed Matter
Journal Volume
51
Journal Issue
1
Journal Page Range
p. 581-588.
ISSN
0163-1829
CODEN
PRBMDO