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arXiv · 1206.5740

Emergent Critical Phase and Ricci Flow in a 2D Frustrated Heisenberg Model

Peter P. Orth·Premala Chandra·Piers Coleman·Jörg Schmalian
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Abstract

We introduce a two-dimensional frustrated Heisenberg antiferromagnet on interpenetrating honeycomb and triangular lattices. Classically the two sublattices decouple, and "order from disorder" drives them into a coplanar state. Applying Friedan's geometric approach to nonlinear sigma models, we show that the scaling of the spin-stiffnesses corresponds to the Ricci flow of a 4D metric tensor. At low temperatures, the relative phase between the spins on the two sublattices is described by a six-state clock model with an emergent critical phase.

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Peter P. Orth, Premala Chandra, Piers Coleman, Jörg Schmalian. 2012-12-12. Emergent Critical Phase and Ricci Flow in a 2D Frustrated Heisenberg Model. https://doi.org/10.1103/physrevlett.109.237205

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