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arXiv · 1507.01126

A new look on the two-dimensional Ising model: thermal artificial spins

Unnar B. Arnalds·Jonathan Chico·Henry Stopfel·Vassilios Kapaklis·Oliver Bärenbold·Marc A. Verschuuren·Ulrike Wolff·Volker Neu·Anders Bergman·Björgvin Hjörvarsson
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Abstract

We present a direct experimental investigation of the thermal ordering in an artificial analogue of an asymmetric two dimensional Ising system composed of a rectangular array of nano-fabricated magnetostatically interacting islands. During fabrication and below a critical thickness of the magnetic material the islands are thermally fluctuating and thus the system is able to explore its phase space. Above the critical thickness the islands freeze-in resulting in an arrested thermalized state for the array. Determining the magnetic state of the array we demonstrate a genuine artificial two-dimensional Ising system which can be analyzed in the context of nearest neighbour interactions.

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Unnar B. Arnalds, Jonathan Chico, Henry Stopfel, Vassilios Kapaklis, Oliver Bärenbold, Marc A. Verschuuren, Ulrike Wolff, Volker Neu, Anders Bergman, Björgvin Hjörvarsson. 2015-07-04. A new look on the two-dimensional Ising model: thermal artificial spins. https://doi.org/10.1088/1367-2630/18/2/023008

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