Wannier states and spin supersolid physics in the triangular antiferromagnet K2Co(SeO3)2
Source abstract
Abstract
We combine ultra-high-resolution inelastic neutron scattering and quantum Monte Carlo simulations to study thermodynamics and spin excitations in the spin-supersolid phase of the triangular lattice XXZ antiferromagnet K 2 Co(SeO 3 ) 2 under zero and non-zero magnetic field. BKT transitions signaling the onset of Ising and supersolid order are clearly identified, and the Wannier entropy is experimentally recovered just above the supersolid phase. At low temperatures, with an experimental resolution of about 23 μeV, no discrete coherent magnon modes are resolved within a broad scattering continuum. Alongside gapless excitations, a pseudo-Goldstone mode with a 0.06 meV gap is observed. A second, higher-energy continuum replaces single-spin-flip excitations of the Ising model. Under applied fields, the continuum evolves into coherent spin waves, with Goldstone and pseudo-Goldstone sectors responding differently. The experiments and simulations show excellent quantitative agreement.
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Research context
OpenAlex topics: Inorganic Fluorides and Related Compounds · Advanced Condensed Matter Physics · Magnetism in coordination complexes
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (74)
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