Anisotropic Hall mobility in slightly overdoped ${\mathrm{YBa}}_2$${\mathrm{Cu}}_3$${\mathrm{O}}_{6.92}$ from magnetoresistance and Hall-coefficient measurements

Hall mobilities of slightly overdoped ${\mathrm{YBa}}_2$${\mathrm{Cu}}_3$${\mathrm{O}}_{6.92}$ crystals were evaluated from the measurements of the in-plane magnetoresistance (MR) and the Hall effects. While MR for H‖c is consistently understood in terms of the in-plane Hall mobility, MR for H‖ab has shown no detectable orbital contribution, which strongly suggests that the Hall mobility involving the c-axis hopping is seriously suppressed. The Hall conductivities are found to be also highly anisotropic, and the anisotropy becomes larger with decreasing temperature, as is similar to the anisotropy of the dc resistivity.