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arXiv · 1903.01160

Continuous ground-state degeneracy of classical dipoles on regular lattices

Dominik Schildknecht·Michael Schütt·Laura J. Heyderman·Peter M. Derlet
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Abstract

Dipolar interactions are crucial in the modeling of many complex magnetic systems, such as the pyrochlores and artificial spin systems. Remarkably, many classical dipolar coupled spin systems exhibit a continuous ground-state degeneracy, which is unexpected as the Hamiltonian does not possess a continuous symmetry. In this paper, we explain, how such a finite point-symmetry leads to a continuous ground-state degeneracy of specific classical dipolar-coupled systems. This work, therefore, provides new insight into the theory of classical dipolar-coupled spin-systems and opens the way to understand more complex dipolar coupled systems.

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Dominik Schildknecht, Michael Schütt, Laura J. Heyderman, Peter M. Derlet. 2019-07-23. Continuous ground-state degeneracy of classical dipoles on regular lattices. https://doi.org/10.1103/physrevb.100.014426

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