【摘要】 对低掺杂区非超导的Pb_6.56Sr_?Y_?Ca_?Cu_?O_y单晶样品进行了电阻和磁阻的测量,发现在低温下电阻温度关系遵从变程跳跃传导的R=R_?exp[(T_?/T)^?]的变化规律,这说明该样品处于强局域化区域.在低温下的磁阻为负并有明显的各向异性,这表明这类体系的磁阻主要来自于轨道效应的贡献,并且可能受到自旋-轨道散射的影响.更多还原

【Abstract】 We have measured resistivity and magnetoresistance of insulating Ca0.25Cu1.7Oy crystals. Moct variable-range-hopping transport R = R0exp[(T0/T)α] has been observed at low temperatures suggesting a strong localization behavior. The magnetoresistance was found to be negative and highly anisotropic, indicating the exsistance of a quantum interference contribution to the MR, which may be influenced by spin-orbit scattering.更多还原