Differential conductance of normal metal-insulator-d-wave superconductor junctions with interface roughness

✍ Scribed by Jian-Xin Zhu; Z.D. Wang; D.Y. Xing; Z.C. Dong

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 447 KB
• Volume: 260
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(96)00053-6

✦ Synopsis

Within the framework of Blonder-Tinkham-Klapwijk (BTK) model and taking into account the interface roughness, we calculate the differential conductance of normal metal-insulator-d-wave superconductor junctions. We find that the tunneling spectrum depends strongly on both the incident angle of electrons and the crystalline axis orientation of the superconductor, and exhibits the zero-bias anomaly under suitable arrangements. Interestingly, even in the absence of the insulating layer, the tunneling spectrum of normal metal-d-wave superconductor junctions differs significantly from that for normal metal-s-wave superconductor due to the interface roughness. Moreover, both the tunnel conductance peak at the energy gap and the zero-bias conductance peak are suppressed by the interface roughness. Our results can explain many experimental measurements on the tunneling spectra of high-To superconductors.

Recently, the symmetry of the pairing state in cuprate high-Tc superconductors has attracted much attention. Many theoretical [1-12] and experimental [13][14][15][16][17] studies have proposed and indicated that the order parameter with a node structure of dx2 x 2 a--b