在正常金属/铁磁绝缘层/正常金属/自旋三重态P波超导隧道结中,考虑到铁磁绝缘层的磁散射和粗糙界面散射,运用Bogoliubov-de Gennes(BdG)方程和Blonder-Tinkham-Klapwijk(BTK)理论模型,研究了铁磁绝缘层对隧道结微分电导的影响.研究表明:(1)对于Px波,粗糙界面散射和磁散射都能使零偏压电导峰变低,能隙处凹陷升高;随着磁散射的增强,谱线的尖锐峰消失,宽峰逐渐变为凹陷;(2)对于Py波,粗糙界面散射和磁散射都能使零能凹陷上移,能隙峰变低,随着粗糙界面散射的增强,两能隙峰间距减小;随着中间正常金属层厚度的增加,能隙内电导随外加偏压呈现振荡行为,能隙外电导仅与普通势垒有关;(3)对于Px+ipy波,随着粗糙界面散射的增强,零偏压电导峰被压低,双凹陷处的值逐渐增大为小的能隙峰,而磁散射并不改变谱线中各凹陷处的电导值.
Using Blonder-Tinkham-Klapwijk (BTK) approach and Bogoliubev-de Gennes (BdG) equation, we have studied, taking into account the magnetic scattering and rough interface scattering, the effect of the ferromagnetic insulator on the conductance in normal metal/ferromagnetic insulator/normal metal/p-wave superconductor (N/FI/Np) junctions. It is found that: ( 1 ) For the p,-wave, the cough interface scattering and the magnetic scattering effect can suppress the zero-bias conductance peak (ZBCP) as well as raise the energy nap dip. As increasing the magnetic scattering, the sharp ZBCP disap-pears and the broad peak will evolve dip. (2) For the py-wave, the cough interface scattering and the magnetic scattering effect can raise the zero-energy dip and suppress the energy gap peak. The distance between the two energy gap peaks de-creases with increasing the cough interface scattering. The conductance in the energy gap exhibit oscillatory behavior while that out the energy gap is a constant with fixed normal potential under the condition of a ferromagnet layer located at the dis-tance several times larger than the coherence length from the superconductor interface. (3) For the px + ipy-wave, the cough interface scattering can suppress the ZBCP and turn the double-dips into litter peaks. The magnetic scattering effect, howev-er, cannot change the value of the conductance at the dips.
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