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采用常规的固相合成法分别制备了Fe3+掺杂和2/3Fe3++1/3Fe2+混合Fe离子掺杂的两组Sr14(Cu1-yFey)24O41系列样品.X射线衍射分析显示,当Fe3+离子的掺杂量y≤0.03以及2/3Fe3++1/3Fe2+混合Fe离子掺杂量y≤0.02时,样品呈较纯的单相,并且对于每组样品,随着掺杂离子含量的增加,样品的晶格常数a,b的值逐渐减小.电输运性质的测试分析表明,Fe3+掺杂系列样品中随Fe3+离子含量的增加,样品的电阻率单调减小,揭示了Cu2O3自旋梯子上的空穴载流子浓度增加.进一步分析显示在电阻与温度关系曲线上存在一个渡越温度Tρ,在Tρ上下Sr14(Cu1-yFey)24O41系统存在两种导电机理在Tρ以上,自旋梯子上单个空穴的热激发对电导有贡献;在Tρ以下,一维配对的局域化的空穴跳跃电导起主要作用.2/3Fe3++1/3Fe2+混合Fe离子掺杂样品的输运性质呈现非单调变化的趋势.讨论给出了掺杂引起晶格常数变化与电输运性质变化的关联机理.
Two series of Sr14 (Cu1-yFey) 24O41 series doped with Fe3 + and Fe doped with 2 / 3Fe3 ++ 1 / 3Fe2 + mixed Fe ions were prepared by the conventional solid-state synthesis method respectively.X-ray diffraction analysis showed that when Fe3 + When the doping amount is less than or equal to y≤0.03 and the doping amount of 2 / 3Fe3 + + 1 / 3Fe2 + mixed Fe ions is less than or equal to 0.02, the samples are pure single phase, and for each sample, with increasing doping ion content, The lattice constants a and b decrease gradually.The test results of the electric transport properties show that the resistivity of the sample decreases monotonously with the increase of Fe3 + content in Fe3 + -doped samples, Of the hole carrier concentration.Further analysis showed that there is a transition temperature Tρ in the relationship between resistance and temperature, there are two kinds of conduction mechanism above Tρ in Sr14 (Cu1-yFey) 24O41 system above Tρ, The thermal excitation of a single hole contributes to the conductance; below Tρ, the one-dimensional localized hole hopping conductance plays a major role. The transport properties for the 2 / 3Fe3 ++ 1 / 3Fe2 + Non-monotonically changing trend. The discussion shows that doping leads to changes in the lattice constant and the nature of the electric transport The association mechanism.