Coexistence of magnetic fluctuations and long-range order in the one-dimensional J(1)-J(2) zigzag chain materials BaDy2O4 and BaHo2O4

Article

关键词: SINGLE-CRYSTAL;    DIFFRACTION;    BALN(2)O(4);    LANTHANIDE;    LN;   

DOI  :  10.1103/PhysRevB.98.144428

来源: SCIE

【 摘 要 】

The compounds BaDy2O4 and BaHo2O4 are part of a family of frustrated systems exhibiting interesting properties, including spin-liquid-type ground states, magnetic-field-induced phases, and the coexistence of short-and long-range magnetic order, with dominant one-dimensional correlations, which can be described as Ising J(1)-J(2) zigzag chains along the c axis. We have investigated polycrystalline samples of BaDy2O4 and BaHo2O4 with both neutron diffraction and neutron spectroscopy, coupled to detailed crystalline electric field calculations. The latter points to site-dependent anisotropic magnetism in both materials, which is corroborated by the magnetic structures we determined. The two systems show the coexistence of two different long-range orders: two double Neel up arrow up arrow down arrow down arrow orders in the ab plane with propagation vectors k(1) = (1/2,0,1/2) and k(2) = (1/2,1/2,1/2) for BaDy2O4, and two distinct arrangements of simple Neel up arrow down arrow up arrow down arrow orders along the c axis, both with the propagation vector k(0) = (0, 0, 0) for BaHo2O4. The order for both wave vectors in BaDy2O4 occurs at T-N = 0.48 K, while in BaHo2O4 the first order sets in at T-N similar to 1.3 K and the second one has a lower ordering temperature of 0.84 K. Both compounds show extensive diffuse scattering which we successfully modeled with a one-dimensional axial next-nearest neighbor Ising (ANNNI) model. In both materials, strong diffusive scattering persists to temperatures well below where the magnetic order is fully saturated.

【 授权许可】

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