【摘要】 测量了不同Bi₂Sr₂CuO_y晶体ab平面内的电阻率-温度变化关系.发现在体系从金属到绝缘体的变化过程中,电子导电首先表现出低温下的二维弱局域化行为,然后逐渐过渡到强局域化的变程跳跃传导行为.依据实验结果对氧化物超导材料在低载流子浓度下的金属—绝缘体转变进行了讨论.更多还原

【Abstract】 The ab-plane resistivity of Bi2Sr2CuO, crystals as a function of temperature has been measured. In the process of metal-insulator transition, the crystals at low temperature exhibit the two-dimensional weak localization behavior at first, and cross over to the variable-range-hopping conduction of the strong localization regime gradually. Discussions on the nature of the metal-insulator transition are presented based on the experimental results.更多还原