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arXiv · 1810.02951

Ripple state in the frustrated honeycomb-lattice antiferromagnet

Tokuro Shimokawa·Hikaru Kawamura
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Abstract

We discover a new type of multiple-$q$ state, "ripple state", in a frustrated honeycomb-lattice Heisenberg antiferromagnet under magnetic fields. The ground state has an infinite ring-like degeneracy in the wavevector space, exhibiting a cooperative paramagnetic state, "ring-liquid" state. We elucidate that the system exhibits the ripple state as a new low-temperature thermodynamic phase via a second-order phase transition from the ring-liquid state, keeping the ring-like spin structure factor. The spin texture in real space looks like a "water ripple" and can induce a giant electric polarization vortex. Possible relationship to the honeycomb-lattice compound, ${\rm Bi_{3}Mn_{4}O_{12}(NO_{3})}$, is discussed.

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Tokuro Shimokawa, Hikaru Kawamura. 2019-06-16. Ripple state in the frustrated honeycomb-lattice antiferromagnet. https://doi.org/10.1103/physrevlett.123.057202

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