Flux pinning in neutron irradiated YBa sub 2 Cu sub 3 O sub 7 minus x

Conference · Fri Mar 01 04:00:00 EST 1991 · IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers); (United States)

OSTI ID:5766237

Lessure, H A; Simizu, S; Baumert, B A; Sankar, S G; McHenry, M E ^[1]; Maley, M P; Cost, J R; Willis, J O ^[2]

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1. Carnegie-Mellon Univ., Pittsburgh, PA (United States)
2. Los Alamos National Lab., NM (United States)

This paper reports on identical polycrystalline samples of YBa{sub 2}Cu{sub 3}O{sub 7{minus}x} irradiated with fast neutrons (E {gt} 0.1 MeV) in eight steps between 0 and 2.1 {times} 10{sup 18} n/cm{sup 2}. Notable irradiation effects include a T{sub c} depression of nearly 2 K at the highest fluence and large improvement in the critical current density for fields from 0-9 T and temperatures between 4-80 K. Critical currents approaching 2 {times} 10{sup 7} A/cm{sup 2} are observed for optimally irradiated materials at 5K (in zero field) while at 77 K, J{sub c} (O kOe) approaches 5 {times} 10{sup 5} A/cm{sup 2}. Irradiation is seen to take a nearly equilibrium magnetization curve at 77 K and broaden it to a significantly hysteretic curve. A substantial shift in the effective pinning potential as a function of current density is inferred from magnetic relaxation measurements at H = 1T. This is the first such measurement in which systematically increased activation energies for flux creep (as a function of current density) are noted.

• OSTI ID: 5766237
• Report Number(s): CONF-900944--
• Conference Information: Journal Name: IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers); (United States) Journal Volume: 27:2
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360206* -- Ceramics
Cermets
& Refractories-- Radiation Effects
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
BARYONS
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
CRITICAL CURRENT
CRYSTALS
CURRENT DENSITY
CURRENTS
ELECTRIC CURRENTS
ELEMENTARY PARTICLES
FAST NEUTRONS
FERMIONS
HADRONS
IRRADIATION
MAGNETIC FLUX
NEUTRONS
NUCLEONS
OXIDES
OXYGEN COMPOUNDS
POLYCRYSTALS
RADIATION EFFECTS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES