Thermal evolution of quasi-one-dimensional spin correlations within the anisotropic triangular lattice of alpha-NaMnO2

Article

关键词: HEISENBERG-ANTIFERROMAGNET;    MAGNETIC-STRUCTURES;    NEUTRON-SCATTERING;    SINGLE-CRYSTALS;    PHASE;    MN3O4;    INHOMOGENEITY;    DIFFRACTION;    FRUSTRATION;    TRANSITION;   

DOI  :  10.1103/PhysRevB.98.144444

来源: SCIE

【 摘 要 】

Magnetic order on the spatially anisotropic triangular lattice of alpha-NaMnO2 is studied via neutron diffraction measurements. The transition into a commensurate, collinear antiferromagnetic ground state with k = (0.5, 0.5, 0) was found to occur below T-N = 22 K. Above this temperature, the transition is preceded by the formation of a coexisting, short-range ordered, incommensurate state below T-IC = 45 K whose two-dimensional propagation vector evolves toward k = (0.5, 0.5) as the temperature approaches T-N. At high temperatures (T > T-IC), quasielastic scattering reveals one-dimensional spin correlations along the nearest-neighbor Mn-Mn chain direction of the MnO6 planes. Our data are consistent with the predictions of a mean-field model of Ising-like spins on an anisotropic triangular lattice, as well as the predominantly one-dimensional Heisenberg spin Hamiltonian reported for this material.

【 授权许可】

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