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Phase-coherence threshold and vortex-glass state in diluted Josephson-junction arrays in a magnetic field

Enzo Granato·Daniel Dominguez
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Abstract

We study numerically the interplay of phase coherence and vortex-glass state in two-dimensional Josephson-junction arrays with average rational values of flux quantum per plaquette $f$ and random dilution of junctions. For $f=1/2$, we find evidence of a phase coherence threshold value $x_s$, below the percolation concentration of diluted junctions $x_p$, where the superconducting transition vanishes. For $x_s < x < x_p$ the array behaves as a zero-temperature vortex glass with nonzero linear resistance at finite temperatures. The zero-temperature critical currents are insensitive to variations in $f$ in the vortex glass region while they are strongly $f$ dependent in the phase coherent region.

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Enzo Granato, Daniel Dominguez. 2000-12-05. Phase-coherence threshold and vortex-glass state in diluted Josephson-junction arrays in a magnetic field. https://doi.org/10.1103/physrevb.63.094507

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