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arXiv · 1509.04593

A numerical study of planar arrays of correlated spin islands

I. Maccari·A. Maiorano·E. Marinari·J. J. Ruiz-Lorenzo
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Abstract

We present our analysis of a system of interacting islands of XY spins on a triangular lattice that has been introduced a few years ago by Eley et al. to account for the phenomenology in experiments on tunable arrays of proximity coupled long superconductor-normal metal-superconductor junctions. The main features of the model are the separation of a local and a global interaction energy scale and the mesoscopic character of the spin islands. Upon lowering the temperature the model undergoes two crossovers corresponding to an increasing phase coherence on a single island and to the onset of global coherence across the array; the latter is a thermodynamical phase transition in the Ising universality class. The dependence of the second transition on the island edge-to-edge spacing is related to the proximity-effect of the coupling constant.

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I. Maccari, A. Maiorano, E. Marinari, J. J. Ruiz-Lorenzo. 2015-09-15. A numerical study of planar arrays of correlated spin islands. https://doi.org/10.1140/epjb/e2016-70171-x

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