Year: 2019
Type: article
Abstract: Magnetism of Cu 2 (OH) 3 Br single crystals based on a triangular lattice is studied by means of magnetic susceptibility, pulsed-field magnetization, and specific heat measurements. There are two inequivalent Cu 2+ sites in an asymmetric unit. Both Cu 2+ sublattices undergo a long-range antiferromagnetic (AFM) order at K. Upon cooling, an anisotropy crossover from Heisenberg to XY behavior is observed below 7.5 K from the anisotropic magnetic susceptibility. The magnetic field applied within the XY plane induces a spin-flop transition of Cu 2+ ions between 4.9 T and 5.3 T. With further increasing fields, the magnetic moment is gradually increased but is only about half of the saturation of a Cu 2+ ion even in 30 T. The individual reorientation of the inequivalent Cu 2+ spins under field is proposed to account for the magnetization behavior. The observed spin-flop transition is likely related to one Cu site, and the AFM coupling among the rest Cu spins is so strong that the 30 T field cannot overcome the anisotropy. The temperature dependence of the magnetic specific heat, which is well described by a sum of two gapped AFM contributions, is a further support for the proposed scenario.
Authors: Z Y Zhao, H L Che, R Chen, J F Wang, X F Sun, Z Z He
Institutions: Chinese Academy of Sciences, Fujian Institute of Research on the Structure of Matter, State Key Laboratory of Structural Chemistry, University of Science and Technology of China, Huazhong University of Science and Technology, Anhui University, Collaborative Innovation Center of Advanced Microstructures
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2952008866