Transport properties and magnetic field induced localization in the misfit cobaltite [Bi\(_2\)Ba\(_{1.3}\)K\(_{0.6}\)Co\(_{0.1}\)]\(^{RS}\)[CoO\(_2\)]\(_{1.97}\) single crystal

Abstract

Resistivity under magnetic field, thermopower and Hall coefficient are systematically studied for [Bi\(_2\)Ba\(_{1.3}\)K\(_{0.6}\)Co\(_{0.1}\)]\(^{RS}\)[CoO\(_2\)]\(_{1.97}\) single crystal. In-plane resistivity (\(\rho_{ab}\)(T)) shows metallic behavior down to 2 K with a \(T^2\) dependence below 30 K; while out-of-plane resistivity (\(\rho_{c}(T)\)) shows metallic behavior at high temperature and a thermal activation semiconducting behavior below about 12 K. Striking feature is that magnetic field induces a ln(1/\(T\)) diverging behavior in both \(\rho_{ab}\) and \(\rho_{c}(T)\) at low temperature. The positive magnetoresistance (MR) could be well fitted by the formula based on multi-band electronic structure. The ln(1/\(T\)) diverging behavior in \(\rho_{ab}\) and \(\rho_{c}(T)\) could arise from the magnetic-field-induced 2D weak localization or spin density wave.