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

• Published in: New journal of physics Vol. 18; no. 2; pp. 23008 - 23015
• Main Authors: Arnalds, Unnar B, Chico, Jonathan, Stopfel, Henry, Kapaklis, Vassilios, Bärenbold, Oliver, Verschuuren, Marc A, Wolff, Ulrike, Neu, Volker, Bergman, Anders, Hjörvarsson, Björgvin
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 29-01-2016
• Subjects: Arrays; artificial spins; Ising model; Islands; Magnetic materials; magnetic ordering; Physics; Thickness; Two dimensional analysis; Two dimensional models; Variation
• ISSN: 1367-2630; 1367-2630
• DOI: 10.1088/1367-2630/18/2/023008

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 we demonstrate a genuine artificial two-dimensional Ising system which can be analyzed in the context of nearest neighbor interactions.