2008/03/31 by R. Nath, Alexander A. Tsirlin, A. A. Tsirlin +3 · 2 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.78.064422
published as Phys. Rev. B 78, 064422 (2008) · 8 pages, 6 figures
arxiv created 2008/08/25 · openalex publication_date 2008/08/25 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We report magnetization and specific-heat measurements on polycrystalline samples of BaCdVO(PO4)2 and show that this compound is a S=1/2 frustrated square lattice with ferromagnetic nearest-neighbor (J1) and antiferromagnetic next-nearest-neighbor (J2) interactions. The coupling constants J1\ensuremath≃\ensuremath-3.6 K and J2\ensuremath≃3.2 K are determined from a fitting of the susceptibility data and confirmed by an analysis of the saturation field (\ensuremathμ0Hs\ensuremath≃4.2 T), the specific heat, and the magnetic entropy. BaCdVO(PO4)2 undergoes magnetic ordering at about 1 K, likely toward a columnar antiferromagnetic state. We find that BaCdVO(PO4)2 with the frustration ratio \ensuremathα=J2/J1\ensuremath≃\ensuremath-0.9 is closer to a critical (quantum spin liquid) region of the frustrated square lattice than any of the previously reported compounds. Positive curvature of the magnetization curve is observed in agreement with recent theoretical predictions for high-field properties of the frustrated square lattice close to the critical regime.