Anisotropic Magnetoresistance in Charge-Ordering $Na_{0.34}(H_3O)_{0.15}CoO_2$:Strong Spin-Charge Coupling and Spin Ordering

C. H. Wang; X. H. Chen; G. Wu; T. Wu; H. T. Zhang; J. L. Luo; G. T. Liu; N. L. Wang

doi:10.1103/PhysRevB.74.172507

paper

Anisotropic Magnetoresistance in Charge-Ordering $N a_{0.34} (H_{3} O)_{0.15} C o O_{2}$ :Strong Spin-Charge Coupling and Spin Ordering

arXiv:cond-mat/0607573 · doi:10.1103/PhysRevB.74.172507

Abstract

Angular-dependent in-plane magnetoresistance (AMR) for single crystal $N a_{0.34} (H_{3} O)_{0.15} C o O_{2}$ with charge ordering is studied systematically. The anisotropic magnetoresistance shows a twofold symmetry at high temperature with rotating H in the Co-O plane, while a sixfold symmetry below a certain temperature ( $T_{I ¨} $ ). At $T_{I ¨} $ , the symmetry of AMR changes from twofold to fourfold with rotating magnetic field (H) in the plane consisting of the current and c-axis. The variation of AMR symmetry with temperature arises from the subtle changes of the spin structure. These results give a direct evidence for the itinerant electrons directly coupled to the localized spins.

4 pages, 4 figures

Anisotropic Magnetoresistance in Charge-Ordering Na0.34​(H3​O)0.15​CoO2​:Strong Spin-Charge Coupling and Spin Ordering

Abstract

Anisotropic Magnetoresistance in Charge-Ordering $N a_{0.34} (H_{3} O)_{0.15} C o O_{2}$ :Strong Spin-Charge Coupling and Spin Ordering