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Scaling of the Hall Resistivity in the Solid and Liquid Vortex Phases in Twinned Single Crystal YBCO

G. D'Anna·V. Berseth·L. Forro·A. Erb·E. Walker
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Abstract

Longitudinal and Hall voltages are measured in a clean twinned YBCO single crystal in the liquid and solid vortex phases. For magnetic fields tilted away from the c-axis more than about 2 deg, a scaling law |rho_xy|=A (rho_xx)^beta with beta approx.=1.4 is observed, which is unaffected by the vortex-lattice melting transition. The vortex-solid Hall conductivity is non-linear and diverges to negative values at low temperature. When the magnetic field is aligned to the c-axis, the twin-boundary correlated disorder modifies the scaling law, and beta approx.=2. The scaling law is unaffected by the Bose-glass transition. We discuss the scaling behaviour in terms of the dimension-dependent theory for percolation in metallic conductors.

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G. D'Anna, V. Berseth, L. Forro, A. Erb, E. Walker. 1999-06-18. Scaling of the Hall Resistivity in the Solid and Liquid Vortex Phases in Twinned Single Crystal YBCO. https://arxiv.org/abs/cond-mat/9811106

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