Magnetic anisotropy in YbAlO3 studied by electron spin resonance

The magnetic anisotropy of the quantum-critical spin-chain system YbAlO$$_3$$is studied in detail in its paramagnetic phase by means of electron spin resonance. We find an uniaxial g factor anisotropy with $$g_\parallel =7.01$$and $$g_\perp = 0.47$$. The existence of two distinct magnetic Yb sites explains the resonance spectra well

PIN-driven auxin transport emerged early in streptophyte evolution

PIN-FORMED (PIN) transporters mediate directional, intercellular movement of the phytohormone auxin in land plants. To elucidate the evolutionary origins of this developmentally crucial mechanism, we analysed the single PIN homologue of a simple green alga Klebsormidium flaccidum. KfPIN functions as a plasma membrane-localized auxin exporter in land plants and heterologous models. While its role in algae remains unclear, PIN-driven auxin export is probably an ancient and conserved trait within streptophytes

One or two gaps in Mo₈Ga₄₁ superconductor? Local Hall-probe magnetometry study

The magnetization properties of the endohedral cluster superconductor Mo8Ga41 are studied by sensitive Hall-probe magnetometry. The temperature dependence of the lower critical magnetic field H-c1 is obtained and compared to theoretical models accounting for single-gap and two-gap superconductivity. Data can be described by both models with minor differences. These results are confronted with our previous measurements which evidence that the system is inherently single-gap s-wave superconductor but minor additional phases are present also in seemingly perfect samples. We discuss how presence of such additional phases with varying size of the penetration depth and H-c1 field is reflected in magnetization measurements which could lead to misinterpretation of the multigap superconductivity in Mo8Ga41

Local Magnetometry of Cu0.064TiSe2Cu_{0.064}TiSe_{2}

Local magnetometry using miniature Hall-probe array was used to study vortex distribution in superconducting single crystal of $Cu_{x}TiSe_{2}$, with x=0.064 and $T_{c}$=3.2 K. We show that vortices after penetration into the sample move towards the center, resulting into a dome-shape field profile. Such a profile is a signature of relatively low pinning. We show that these measured profiles are consistent with a model proposed for the samples in the absence of bulk pinning. Modifications necessary to obtain quantitative agreement between the model and the data are presented

Observation of a transverse Meissner effect in CuxTiSe2 single crystals

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Weyl Nodes Close to the Fermi Energy in NbAs

The noncentrosymmetric transition-metal monopnictides NbP, TaP, NbAs, and TaAs are a family of Weyl semimetals in which pairs of protected linear crossings of spin-resolved bands occur. These so-called Weyl nodes are characterized by integer topological charges of opposite sign associated with singular points of Berry curvature in momentum space. In such a system, anomalous magnetoelectric responses are predicted, which should only occur if the crossing points are close to the Fermi level and enclosed by Fermi surface pockets penetrated by an integer flux of Berry curvature, dubbed Weyl pockets. TaAs is shown to possess Weyl pockets, whereas TaP and NbP have trivial pockets enclosing zero net flux of Berry curvature. Herein, via measurements of the magnetic torque, resistivity, and magnetization, a comprehensive quantum-oscillation study of NbAs is presented, the last member of this family where the precise shape and nature of the Fermi surface pockets is still unknown. Seven distinct frequency branches, three of which have not been observed before, are detected. A comparison with density functional theory calculations suggests that the two largest pockets are topologically trivial, whereas the low frequencies might stem from tiny Weyl pockets. The enclosed Weyl nodes are within a few meV of the Fermi energy. © 2021 The Authors. physica status solidi (b) basic solid state physics published by Wiley-VCH GmbH

Magnetic and thermodynamic properties of CuxTiSe2 single crystals

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