Codimension-two spiral spin liquid in the effective honeycomb-lattice compound Cs3⁢Fe2⁢Cl9

Journal Article · Wed Apr 01 00:00:00 EDT 2026 · Physical Review B

DOI:https://doi.org/10.1103/zm32-s2xz· OSTI ID:3030534

Gao, Shang ^[1]; Pasco, Chris ^[1]; Omar, Otkur ^[2]; Zhang, Qiang ^[1]; Pajerowski, Daniel M ^[1]; Ye, Feng ^[1]; Frontzek, Matthias D ^[1]; May, Andrew F ^[1]; Stone, Matthew B ^[1]; Christianson, Andrew ^[1]

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1. ORNL
2. Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, People’s

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 Cs3⁢Fe2⁢Cl9, which demonstrates an alternate 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.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 3030534
• Journal Information: Physical Review B, Journal Name: Physical Review B Journal Issue: 14 Vol. 113
• Country of Publication: United States
• Language: English