Scaling of the Hall resistivity in the solid and liquid vortex phases in twinned single-crystalYBa2Cu3O7−δ

Abstract

Longitudinal and Hall voltages are measured in a clean twinned ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ single crystal in the liquid and solid vortex phases. For magnetic fields tilted away from the c axis more than about 2\ifmmode^\circ\else\textdegree\fi{}, a scaling law $|{\ensuremath{\rho}}_{\mathrm{xy}}|=A{\ensuremath{\rho}}_{\mathrm{xx}}^{\ensuremath{\beta}}$ with \ensuremath{\beta}\ensuremath{\approx}1.4 is observed, which is unaffected by the vortex-lattice melting transition. The vortex-solid Hall conductivity is nonlinear 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 \ensuremath{\beta}\ensuremath{\approx}2. The scaling law is unaffected by the Bose-glass transition. We discuss the scaling behavior in terms of a dimension-dependent percolation theory. The twin-boundary guided vortex motion is also investigated.