磁交换作用对铁磁/d_(x^2-y^2)+id_(xy)混合波超导结隧道谱的影响  

Effects of the magnetic exchange interaction on the tunneling spectra in the ferromagnet /d_(x^2-y^2)+id_(xy) mixed wave superconductor junctions

作　　者：吉跃仁[1] 

机构地区：[1]江苏财经职业技术学院,江苏淮安223001

出　　处：《华中师范大学学报（自然科学版）》2007年第1期43-47,共5页Journal of Central China Normal University：Natural Sciences

基　　金：江苏省教育厅自然科学基金资助项目(04KJD140036)

摘　　要：考虑到铁磁层中的磁交换作用和界面势垒的散射效应,利用推广的Blonder-Tinkham-Klapwijk散射理论,计算了铁磁/dx2-y2+idxy混合波超导结中的准粒子输运系数和自旋极化的隧道谱.研究表明:(1)铁磁/dx2-y2+idxy混合波超导结中自旋极化的隧道谱能较好地解释La2/3Ba1/3MnO3/DyBa2Cu3O7隧道结中观察到的零偏压电导凹陷的实验结果;(2)在Δ2/Δ1=1的情况下,磁交换作用和界面势垒散射可压低峰值,且导致隧道谱逐渐演化出四个电导峰;(3)虚的Andreev反射过程对铁磁/dx2-y2+idxy混合波超导结的隧道谱有显著影响.Taking into account the exchange interaction in ferromagnet and the scattering effects of interface barrier, using extended Blonder-Tinkham-Klapwijk scattering theory, we calculate the quasiparticle transport coefficients and the spin-polarized tunneling spectra in the ferromagnet/dx^2-y^2 ＋idxy wixed wave superconductor juntions. It is found that. （1） The spin-polarized tunneling spectra in the ferromagnet /dx^2-y^2＋idxy wixed wave superconductor juntions can explain well experimental measurements of the conductance dip at zero-bias observed in La2/3Ba1/3MnO3/DyBa2Cu3O7 junctions; （2） When△2/△1 is one, the magnetic exchange interaction and interface barrier scattering may suppress the conductance peaks and evolve four conductance peaks in the tunneling spectra （3） The imaginary Andreev reflection have influence notably on the tunneling spectra in the ferromagnet/dx^2-y^2idxy mixed wave supercondrctor junctions.

关 键 词：磁交换作用 dx^2-y^2+idxy如混合波超导体 隧道谱 

分 类 号：O511.4[理学—低温物理]