Two-dimensional magnetism in alpha-CuV2O6

Article

关键词: SPIN-EXCHANGE INTERACTIONS;    DIMER;   

DOI  :  10.1103/PhysRevB.102.014436

来源: SCIE

【 摘 要 】

Several previous studies reported that a one-dimensional Heisenberg chain model is inadequate in describing the magnetic properties of the low-dimensional quantum antiferromagnet alpha-CuV2O6, but the origin for this observation has remained unclear. We have reinvestigated the magnetic properties of alpha-CuV2O6 and found that our anisotropic magnetic susceptibility, neutron-powder diffraction, and electron paramagnetic spin-resonance measurements are in good agreement with extensive density-functional theory (DFT + U) total energy calculations which indicate that the correct spin lattice model for alpha-CuV2O6 is rather a S = 1/2 2D-Heisenberg antiferromagnetic lattice. The magnetic susceptibility data are well described by a rectangular Heisenberg antiferromagnet with anisotropy ratio alpha similar to 0.7 consistent with the DFT results. Quantum Monte Carlo simulations of the magnetic susceptibilities for a rectangular lattice Heisenberg antiferromagnet were performed in the anisotropy range 0.5 <= alpha <= 1.0. The results of the Quantum Monte Carlo calculations were cast into a Pade approximant which was used to fit the temperature-dependent magnetic susceptibility data. Neutron-powder-diffraction measurements were used to conclusively solve the collinear antiferromagnetic structure of alpha-CuV2O6 below the Neel temperature of similar to 22.4 K.

【 授权许可】

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