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arXiv:1301.0853 · Physical Review Letters

Deconfined Criticality in the Frustrated Heisenberg Honeycomb Antiferromagnet

R. Ganesh, Jeroen van den Brink, Satoshi Nishimoto

Published Mar 18, 2013• 108 citations
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Abstract

Using the density matrix renormalization group, we determine the phase diagram of the spin-1/2 Heisenberg antiferromagnet on a honeycomb lattice with a nearest-neighbor interaction J(1) and a frustrating, next-nearest-neighbor exchange J(2). As frustration increases, the ground state exhibits Néel, plaquette, and dimer orders, with critical points at J(2)/J(1) = 0.22 and 0.35. We observe that both the spin gap and the corresponding order parameters vanish continuously at both the critical points, indicating the presence of deconfined quantum criticality.

DOI
10.1103/physrevlett.110.127203

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