绝缘层方势垒影响下N/I/自旋三重态p波超导体结的隧道谱  

TUNNEL SPECTRA IN NORMAL METAL/INSULATOR/SPIN-TRIPLET p-WAVE SUPERCONDUCTOR JUNCTIONS UNDER THE INFLUENCE OF INSULATOR SQUARE BARRIER

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：《低温物理学报》2011年第1期65-72,共8页Low Temperature Physical Letters

摘　　要：以方势垒描述正常金属/绝缘层/自旋三重态p波超导结中绝缘层对准粒子输运的影响,通过求解Bogoliubov-de Gennes(BdG)方程,利用Blonder-Tinkham-Klapwijk(BTK)理论,计算了p波超导结的隧道谱.研究表明:(1)绝缘层厚度的增加,可导致自旋三重态p波超导结隧道谱中出现亚能隙共振峰,粗糙界面散射和杂质散射均对亚能隙共振产生影响;(2)对于px波结,粗糙界面散射和杂质散射均能使零偏电导峰变成凹陷,杂质散射能引起零偏电导峰的劈裂;(3)对于py波结,绝缘层厚度和杂质散射的变化均能在能隙内产生阶梯状的谱形,粗糙界面散射和杂质散射均能使谱线中的零偏电导凹陷上升为峰;(4)对于px+ipy波结,绝缘层厚度和粗糙界面散射均可导致双凹陷结构的消失和小的能隙峰的出现,它们的变化对零偏压处是峰还是凹陷产生直接影响;杂质散射能使零偏电导峰出现劈裂,并使零能凹陷和能隙处的双凹陷加深.Using the square barrier to describe the influence of the insulating layer on the quasi-particle transport in the normal metal/ insulating layer/ spin-triplet p（N/I/p）-wave superconductor junctions,we calculate the tunnel spectra utilizing the Bogoliubov-de Gennes（BdG） equation and Blonder-Tinkham-Klapwijk（BTK） theory.It is shown that： （1） with increasing of insulating layer thickness,the subgap resonance peaks appear in the tunnel spectra of N/I/p-wave superconductor junction,the the subgap resonance is influenced by the rough interface scattering and impurities scattering yet;（2） for the px-wave junction,the zero-bias conductance peak （ZBCP） can be changed into the zero-bias conductance dip（ZBCD） by the rough interface scattering and impurities scattering,and the impurities scattering may cause the splitting of the ZBCP;（3） for the py-wave junction,the variation of the insulating layer thickness and impurities scattering can result in the appearance of staircase in the tunnel spectra,and the rough interface scattering and impurities scattering may change the ZBCD into the ZBCP;（4） for the px＋ipy-wave junction,the insulating layer thickness and rough interface scattering can lead to the disappearance of double-minimum structures and the appearance of small energy gap peaks,the peak or dip in the tunnel spectra at zero-bias is directly influenced by that;the impurities scattering can bring about the splitting of the ZBCP and the deepening of the ZBCD along with the double-minimum structures.

关 键 词：方势垒 N/I/p波超导结 隧道谱 

分 类 号：O511[理学—低温物理]