paper

Quantum Spin Supersolid as a precursory Dirac Spin Liquid in a Triangular Lattice Antiferromagnet

arXiv:2304.11716 · doi:10.1103/PhysRevResearch.6.033031

Abstract

Based on the recent experiments on the triangular lattice antiferromagnet Na $_{2}$ BaCo(PO $_{4}$ ) $_{2}$ , we propose the easy-axis XXZ spin-1/2 model on the triangular lattice, that exhibits a quantum spin supersolid, to be a precursory Dirac spin liquid. Despite the presence of a three-sublattice magnetic order as a spin supersolid, we suggest that this system is close to a Dirac spin liquid by exploring its spectroscopic response. The physical consequence is examined from the spectroscopic response, and we establish the continuous spectra near the M point in addition to the K point excitation from the spinon continuum on top of the three-sublattice order. Moreover, the satellite peaks were predicted at the mid-points connecting the $I^$ and K points. This proposal offers a plausible understanding of the recent inelastic neutron scattering measurement in Na $_{2}$ BaCo(PO $_{4}$ ) $_{2}$ and could inspire further research in relevant models and materials, such as K $_{2}$ Co(SeO $_{3}$ ) $_{2}$ and Rb $_{2}$ Co(SeO $_{3}$ ) $_{2}$ , and even more anisotropic magnets like PrMgAl $_{11}$ O $_{19}$ .

13 pages, 9 figures. To appear in Phys Rev Research