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arXiv · 2405.18973

Codimension-Two Spiral Spin-Liquid in the Effective Honeycomb-Lattice Compound Cs$_3$Fe$_2$Cl$_9$

Shang Gao·Chris Pasco·Otkur Omar·Qiang Zhang·Daniel M. Pajerowski·Feng Ye·Matthias Frontzek·Andrew F. May·Matthew B. Stone·Andrew D. Christianson
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Abstract

A codimension-two spiral spin-liquid is a correlated paramagnetic state with one-dimensional ground state degeneracy hosted within a three-dimensional lattice. Here, via neutron scattering experiments and numerical simulations, we establish the existence of a codimension-two spiral spin-liquid in the effective honeycomb-lattice compound Cs$_3$Fe$_2$Cl$_9$, which demonstrates a novel path to spiral spin-liquids by overcoming the long-standing impediment of weak further-neighbor interactions. In the long-range ordered regime, competing spiral and spin density wave orders emerge as a function of applied magnetic field, among which a possible order-by-disorder transition is identified.

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Shang Gao, Chris Pasco, Otkur Omar, Qiang Zhang, Daniel M. Pajerowski, Feng Ye, Matthias Frontzek, Andrew F. May, Matthew B. Stone, Andrew D. Christianson. 2024-05-29. Codimension-Two Spiral Spin-Liquid in the Effective Honeycomb-Lattice Compound Cs$_3$Fe$_2$Cl$_9$. https://doi.org/10.1103/zm32-s2xz

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