2025/04/28 by Christoph Resch, Georg Benka, Resch, Christoph +5
Materials Science · Physics and Astronomy · #Boron and Carbon Nanomaterials Research #FOS: Physical sciences #Rare-earth and actinide compounds #Strongly Correlated Electrons (cond-mat.str-el) #Superconductivity in MgB2 and Alloys
paper · pdf · doi:10.48550/arxiv.2504.20149
openalex publication_date 2025/04/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We report a study of single crystals of the hexagonal rare-earth diboride ErB2 prepared by means of the self-adjusted flux travelling-solvent floating-zone technique. Measurements of the magnetization, ac susceptibility, specific heat, and electrical resistivity consistently establish ferromagnetic order of the Er3+ moments below a second-order phase transition at Tc = 14~K and a very strong easy-plane anisotropy. Curie--Weiss fits of the ac susceptibility are characteristic of ferromagnetic coupling within the easy hexagonal basal plane, and antiferromagnetic coupling along ⟨001⟩. Under magnetic field within the basal plane the magnetization is reminiscent of a soft ferromagnet that is polarized in fields above a few tenth of a Tesla, vanishing hysteresis and negligible in-plane anisotropy. Under field along ⟨001⟩, typical hard-axis behavior is observed with the magnetization increasing only weakly up to a spin-flip transition at μ0Hc = 12~T. The easy-plane anisotropy emerges below a crossover temperature Tx ≈ 50~K , i.e. a broad paramagnetic temperature range above Tc is governed by strongly anisotropic magnetic fluctuations.