【摘要】 本文通过对Nd_1.85Ce_0.15CuO_4±δ单晶ab面（ρab）和c方向电阻率（ρc）的测量,发现未经过氮气退火的样品的ρc与温度成线性依赖关系,但是同一个样品经过氮气退火后的ρc中不仅有一次方的温度依赖关系还有二次方的.这说明样品经过氮气退火后,电子与空穴两种载流子共同参与导电.样品在退火处理前的各向异性比（ρc-ρc0）/（ρab-ρab0）存在强的温度依赖关系,这是由于ρc与温度成线性依赖关系,然而ρab不仅有一次方的温度依赖关系还有二次方的.样品经过退火处理后的各向异性比存在弱的温度依赖赖关系,这是由于ρc与ρab中都同时有一次方和二次方的温度依赖关系.我们用电子和空穴沿c方向有不同的隧穿几率来解释ρc和（ρc-ρc0）/（ρab-ρab0）.更多还原

【Abstract】 Both in-plane(ρab) and out-of-plane resistivities(ρc) are investigated on Nd1.85Ce0.15CuO4±δ single crystal.The variation of ρc from linear T dependence in as-grown curve to the appearance of T2 component in 2 hours curve is observed,and the ρc decreases simultaneously.This behavior is the distinct evidence that two kinds of charge carriers coexist after annealing treatment.The ratio(ρc-ρc0)/(ρab-ρab0) of the as-grown curve shows a strong temperature dependence,due to the linear T dependence in ρc while the coexistence of T and T2 dependences in ρab.Contrarily,the ratios of annealed curves show the weak temperature dependence,attributed to the coexistence of T and T2 dependences in ρc and ρab.We use the different tunneling rates of electrons and holes along the c axis to explain the behavior of ρc and the high(ρc-ρc0)/(ρab-ρab0).更多还原