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DOE OSTI · 1853089

Frustrated spin-1/2 dimer compound K 2 Co 2 ( Se O 3 ) 3 with easy-axis anisotropy

Zhong, Ruidan·Guo, Shu·Nguyen, Loi T.·Cava, Robert J.
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Abstract

Magnetic susceptibility, magnetization, and specific-heat measurements under both in-plane and out-of-plane field on K 2 Co 2 (SeO 3 ) 3 single crystals are reported. The Co dimers in this compound, which are made from face-sharing effective spin-1/2 CoO 6 octahedra, sit on the corners of a geometrically frustrating triangular planar lattice. No long-range magnetic ordering is found down to 0.35 K, which, together with the large negative Curie-Weiss temperature obtained from fitting the temperature-dependent magnetic susceptibility, indicates that the system is magnetically frustrated. Analysis of the field and orientation dependence of the magnetic and thermodynamic properties suggests the presence of an easy-axis anisotropy. Furthermore, the magnetic fluctuations present due to geometric frustration are more resistant to an in-plane field than a perpendicular-to-plane field.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYCrystal structureFrustrated magnetismMagnetic anisotropyMagnetic orderMagnetization measurementsMaterials sciencePhysicsSpecific heat measurementsSusceptibility measurements

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Zhong, Ruidan, Guo, Shu, Nguyen, Loi T., Cava, Robert J.. 2020-12-24. Frustrated spin-1/2 dimer compound K 2 Co 2 ( Se O 3 ) 3 with easy-axis anisotropy. https://doi.org/10.1103/physrevb.102.224430

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