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arXiv · 1510.01448

Classical spin-liquid on the maximally frustrated honeycomb lattice

J. Rehn·Arnab Sen·Kedar Damle·R. Moessner
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Abstract

We show that the honeycomb Heisenberg antiferromagnet with $J_1/2=J_2=J_3$, where $J_{1/2/3}$ are first-, second- and third-neighbour couplings respectively, forms a classical spin liquid with pinch-point singularities in the structure factor at the Brillouin zone corners. Upon dilution with non-magnetic ions, fractionalised degrees of freedom carrying $1/3$ of the free moment emerge. Their effective description in the limit of low-temperature is that of spins randomly located on a triangular lattice, with a frustrated interaction of long-ranged logarithmic form. The XY version of this magnet exhibits nematic thermal order by disorder, which comes with a clear experimental diagnostic.

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J. Rehn, Arnab Sen, Kedar Damle, R. Moessner. 2015-10-06. Classical spin-liquid on the maximally frustrated honeycomb lattice. https://doi.org/10.1103/physrevlett.117.167201

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