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تسجيل مستخدم جديدHall effect and symmetry breaking in non-magnetic metal with dynamic charge stripes
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A comprehensive study of magnetoresistance and Hall effect has been performed for the set of the single crystals of non-magnetic metal LuB12 with the Jahn-Teller instability of the boron cage and dynamic charge stripes forming along <110> direction. Anomalous positive contribution to Hall effect for particular direction of magnetic field H//[001] is found in the single crystals of LuB12 of the highest quality. This contribution arising at T~ 150 K is shown to increase drastically when approaching the disordered ground state below 60 K. The Hall effect anomaly is shown to appear in combination with the peak of magnetoresistance. The various scenarios allowing for the topology of Fermi surface, anisotropy of relaxation time for charge carriers and the filamentary structure of fluctuating charge stripes are proposed to explain the features of magnetotransport in this metal with inhomogeneous distribution of electron density. The origin of SdH oscillations, which are observed in this non-equilibrium metal with electron phase separation and strong charge carrier scattering, is discussed.
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Precise angle-resolved magnetoresistance (ARM) measurements are applied to reveal the origin for the lowering of symmetry in electron transport and the emergence of a huge number of magnetic phases in the ground state of antiferromagnetic metal HoB12
with fcc crystal structure. By analyzing of the polar H-theta-phi magnetic phase diagrams of this compound reconstructed from the experimental ARM data we argue that non-equilibrium electron density oscillations (dynamic charge stripes) are responsible for the suppression of the indirect RKKY exchange along <110> directions between the nearest neighboring magnetic moments of Ho3+ ions in this strongly correlated electron system.
Precise angle-resolved magnetoresistance and magnetization measurements have revealed (i) strong charge transport and magnetic anisotropy and (ii) emergence of a huge number of magnetic phases in the ground state of TmB12 antiferromagnetic metal with
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The model strongly correlated electron system Ho0.8Lu0.2B12 which demonstrates a cooperative Jahn-Teller instability of the boron sub-lattice in combination with rattling modes of Ho(Lu) ions, dynamic charge stripes and unusual antiferromagnetic (AF)
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The insulator-to-metal transition continues to be a challenging subject, especially when electronic correlations are strong. In layered compounds, such as La2-xSrxNiO4 and La2-xBaxCuO4, the doped charge carriers can segregate into periodically-spaced
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