Subhadeep Bej | Searcharxiv

arXiv2026

Complex field-induced magnetic phases and anisotropic magnetotransport in off-stoichiometric CeCuBi2

We report a detailed study on the structural, angle-dependent magnetic and magnetotransport properties of highly anisotropic off-stoichiometric CeCuBi2 single crystals. Our results reveal CeCuBi2 as an anisotropic Kondo antiferromagnet exhibiting complex field-induced magnetic behavior and unusual magnetotransport properties. Magnetic susceptibility and specific heat measurements reveal antiferromagnetic (AFM) ordering below TN = 14 K with strong anisotropy and weak heavy-fermion behavior. Electrical transport measurements show highly anisotropic resistivity and a broad hump around 47 K, indicative of Kondo-driven heavy-fermion behavior. Magnetization measurements reveal multiple field-induced metamagnetic phases, while AC susceptibility measurements indicate slow spin dynamics and spin-glass-like behavior in intermediate field-induced magnetic states. Furthermore, we observe large and strongly anisotropic magneto transport responses, including room-temperature magnetoresistance of approximately 22% at 300 K and 9 T and butterfly-like anisotropic magnetoresistance with AMR values reaching approximately 10.9%. These results highlight a strong interplay among Kondo correlations, magnetic anisotropy, and field-tunable spin configurations, making CeCuBi2 a possible platform for exploring correlated and anisotropic quantum phenomena.

cond-mat.str-el↗

arXiv2025

Ultrahigh Anomalous Nernst Thermopower and Thermal Hall Angle in YbMnBi2

Thermoelectrics (TEs) are solid-state devices that can realize heat-electricity conversion. Transverse TEs require materials with a large Nernst effect, which typically requires a strong applied magnetic field. However, topological materials with magnetic order offer an alternative pathway for achieving large Nernst via the anomalous Hall effect and the accompanying anomalous Nernst effect (ANE) that arise from band topology. Here, we show that YbMnBi2 with a low Hall density and a chemical potential near the Weyl points has, to the best of our knowledge, the highest ANE-dominated Nernst thermopower of any magnetic material, with $S_{yx}$ around 110 $\mu$V/K ($T$ = 254 K, 5 T < $|\mu_0 H|$ < 9 T applied along the spin canting direction), due to the synergism between classical contributions from filled electron bands, large Hall conductivity of topological origin, and large resistivity anisotropy. An appreciable thermal Hall angle of $0.02 < (\nabla_y T)/(\nabla_x T) < 0.06$ was observed (40 K < $T$ < 310 K, $\mu_0 H$ = 9 T).

cond-mat.mtrl-sci↗