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arXiv · 0810.2378

Finite-Temperature Néel Ordering of Fluctuations in a Plaquette Orbital Model

Sandro Wenzel·Wolfhard Janke
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Abstract

We present a pseudospin model which should be experimentally accessible using solid-state devices and, being a variation on the compass model, adds to the toolbox for the protection of qubits in the area of quantum information. Using Monte Carlo methods, we find for both classical and quantum spins in two and three dimensions Ising-type Neel ordering of energy fluctuations at finite temperatures without magnetic order. We also readdress the controversy concerning the stability of the ordered state in the presence of quenched impurities and present numerical results which are at clear variance with earlier claims in the literature.

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Sandro Wenzel, Wolfhard Janke. 2009-08-10. Finite-Temperature Néel Ordering of Fluctuations in a Plaquette Orbital Model. https://doi.org/10.1103/physrevb.80.054403

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