考虑到铁磁层中的磁交换作用, 以及界面的粗糙散射效应,利用推广的Blonder-Tinkham-Klapwijk理论模型,计算铁磁-高Tc氧化物超导结中的隧道谱.研究表明：（1）铁磁层中的磁交换能能压低零偏压电导峰的高度，并能感应出零偏压电导凹陷；（2）粗糙界面散射除了能压低零偏压电导峰，还能使零偏压凹陷处感应出一中心峰.该结果能较好地解释最近的两篇关于La2/3Ba1/3MnO3/DyBa2Cu3O7与La2/3Ba1/3MnO3/YBa2Cu3O7-δ结中隧道谱的实验报道.
Taking into account the exchange interaction in the ferromagnet and rough interface scattering effect, within Blonder-Tinkham-Klapwijk scattering formalism, we calculate the tunnel spectrum in the ferromagnet-high Tc superconductor junctions. It is shown that, (1) the ferromagnetic exchange interaction can decrease the height of the zero-bias conductance peak and may induce a zero-bias conductance dip, (2) the interface roughness can induce a small central peak in the zero-bias conductance dip as well as can decrease the height of the zero-bias conductance peak. The calculate results can account for the tunnel spectrum observed experimentally in and junctions.
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