Vortex pinning by disordered columnar defects in large Josephson junctions

Journal Article · Wed May 01 04:00:00 EDT 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.53.R11949· OSTI ID:283920

Itzler, M A; Tinkham, M ^[1]

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1. Department of Physics and Division of Applied Sciences, Harvard University, Cambridge, Massachusetts 02138 (United States)

To study the pinning of Josephson vortices by well-characterized correlated disorder, we have fabricated and made measurements on a series of large Josephson junctions with lithographically defined parallel columnar defects arranged with varying degrees of positional disorder. Commensurability between vortices and a periodic array of defects gives rise to sharp peaks in {ital I}{sub {ital c}}({ital H}). Randomly shifting the defects from initially periodic positions causes the decay of these commensurate peaks as well as the emergence of a randomly fluctuating background with an oscillatory envelope. Completely random defect placement induces similar {ital I}{sub {ital c}} fluctuations with weaker envelope oscillations. Using a model based on the blocking of Josephson currents by the defects, we have performed numerical calculations which accurately reproduce {ital I}{sub {ital c}}({ital H}) for any given defect configuration and provide a physical understanding of its essential features. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 283920
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 18 Vol. 53; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
CRITICAL FIELD
CRYSTAL DEFECTS
DEFECT STATES
FLUCTUATIONS
JOSEPHSON JUNCTIONS
MAGNETIC FLUX
NUMERICAL SOLUTION
PINNING
RANDOMNESS