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Updated: Jun 3, 2026

Phase Diagram Characterization Using Magnetic Beads as Liquid Carriers
Published on: September 4, 2015
The phase diagram of the Heisenberg antiferromagnet with four-spin interactions
1Department of Physics, Indiana University, Bloomington, IN 47405, USA.
Abstract:
We study the quantum phase diagram of the Heisenberg planar antiferromagnet with a subset of four-spin ring exchange interactions, using the recently proposed hierarchical mean-field approach. By identifying relevant degrees of freedom, we are able to use a single variational ansatz to map the entire phase diagram of the model and uncover the nature of its various phases. It is shown that there exists a transition between a Néel state and a quantum paramagnetic phase, characterized by broken translational invariance. The non-magnetic phase preserves the lattice rotational symmetry, and has a correlated plaquette nature. Our results also suggest that this phase transition can be properly described within the Landau paradigm.
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