纳米NiAl合金的输运性质与电子局域化  

THE TRANSPORT PROPERTIES AND LOCALIZATION OF ELECTRONS IN NANOSTRUCTURED NiAl ALLOYS

作　　者：吴柏枚[1] 杨东升[1] 阮可青[1] 盛松[1] 冯宇[1] 曹烈兆[1] 秦晓英[2] 

机构地区：[1]中国科学技术大学物理系 [2]中国科学院固体物理所

出　　处：《低温物理学报》1997年第6期432-436,共5页Low Temperature Physical Letters

基　　金：高等学校博士学科点专项科研基金

摘　　要：测量了不同相对密度的纳米ＮｉＡｌ合金在４．２～７７Ｋ温度范围的电阻率和部分磁阻．实验发现纳米ＮｉＡｌ合金的电阻温度系数随相对密度的减小由正变到负，在相对密度７０％的样品中出现电阻极小．分析指出具有负温度系数的样品的导电是变程跳跃导电．结果表明材料纳米化后电阻率的变化不仅反映了界面体积增大而导致电阻率增大，而且也反映了纳米化后传导电子局域化，以及磁散射对纳米ＮｉＡｌ合金输运性质的影响．The electrical resistance and magnetic resistance of nanostructured NiAl alloys have been measured in the temperature range between 4.2 and 77 K. The different temperature relationship of resistance for specimens with different relative density are observed. A minimum in resistance is also observed at low temperature in nanostructured NiAl alloy with 70% relative density. It is found that the negative temperature coefficient in resistance for specimens with less than 70% relative density indicated the existence of transmit electric current by jumping between local states in this temperature range. The results shows electrical transport properties in nanostructured NiAl alloys are related to the nanostructure, localization of electrons, as well the magnetic contribution.

关 键 词：输运性质 电子局域化 纳米合金 NIAL合金 

分 类 号：TG146.15[一般工业技术—材料科学与工程] TG111[金属学及工艺—金属材料]