Monte Carlo simulations of Josephson-junction arrays with positional disorder

Journal Article · Tue May 01 00:00:00 EDT 1990 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.41.8749· OSTI ID:7093910

Forrester, M G; Benz, S P; Lobb, C J ^[1]

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1. Department of Physics, Harvard University, Cambridge, MA (USA) Division of Applied Sciences, Harvard University, Cambridge, MA (USA)

We present the results of Monte Carlo simulations of Josephson-junction arrays with positional disorder, in magnetic fields such that the average number of flux quanta per unit cell is an integer. Granato and Kosterlitz have predicted that such systems should exhibit novel behavior, including a disorder-dependent critical field and a reentrant Kosterlitz-Thouless transition. We find that, for magnetic fields above a field approximately equal to the theoretical critical field, the superconducting phases become essentially randomized for all temperatures, rather than becoming aligned as the temperature decreases. Our results show no clear evidence for a reentrant phase transition in our small (16{times}16) simulated system. These results are consistent with our experiments on proximity-effect arrays with controlled positional disorder. We suggest that the theoretically proposed reentrance is prevented by either finite-size effects or pinning of vortices due to the disorder.

• OSTI ID: 7093910
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 41:13; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

656100* -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
HAMILTONIANS
JOSEPHSON JUNCTIONS
JUNCTIONS
MAGNETIC FIELDS
MATHEMATICAL OPERATORS
MONTE CARLO METHOD
PROXIMITY EFFECT
QUANTUM OPERATORS
SIMULATION
SUPERCONDUCTING JUNCTIONS
VORTICES