Electronic transport in the ferromagnetic pyrochlore Lu2V2O7: Role of magnetization

Article

关键词: CARRIER DENSITY FERROMAGNET;    COLOSSAL-MAGNETORESISTANCE;    DOUBLE-EXCHANGE;    SPIN ICE;    GIANT MAGNETORESISTANCE;    GEOMETRICAL FRUSTRATION;    HOPPING CONDUCTION;    SINGLE-CRYSTALS;    LA1-XSRXMNO3;    MAGNETOTRANSPORT;   

DOI  :  10.1103/PhysRevB.91.205107

来源: SCIE

【 摘 要 】

This paper reports on a study of the resistivity and Hall effect of the ferromagnetic pyrochlore Lu2V2O7. The temperature dependence of the resistivity of single crystalline Lu2V2O7 exhibits overall activation behavior with a metalliclike exception at intermediate temperatures near the Curie temperature (T-C). This temperature dependence bears a surprising resemblance to that of doped semiconductors. The ferromagnetic oxide shows a negative magnetoresistance (MR) which scales quadratically with the reduced magnetization at temperatures above T-C; however, the scaling factor is significantly smaller than the value expected for a ferromagnetic system in the pure spin scattering regime, which suggests that other scattering processes may be at work. Concomitant with the negative MR, a distinct switch in the Hall resistivity slope is observed at temperatures near T-C. Our analysis suggests that the nonlinear Hall effect is associated with a change in the effective carrier density at a constant critical magnetization induced by an external magnetic field. We argue that within a picture that incorporates high temperature activation transport with a magnetization-driven charge percolation transition, the observed complex electronic transport in the ferromagnetic pyrochlore can be quantitatively described.

【 授权许可】

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