Zeeman effects on d-wave superconductor and the coherent tunneling spectrum in normal-metal/ d-wave superconductor/normal-metal tunnel junctions

• Published in: Solid state communications 2007-06, Vol.142 (10), p.577-582
• Main Author: Dong, Z.C.
• Format: Article
• Language: English
• Subjects: A. d-wave superconductor; D. Coherent tunneling spectrum; E. Zeeman effects
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2007.04.002

We solve a self-consistent equation for the d-wave superconducting gap and the magnetization in the mean-field approximation, study the Zeeman effects on the thermodynamic potential of d-wave superconductor (S) and coherent quantum transport in normal-metal (N)/ d-wave S/N double tunnel junctions. Taking simultaneously into account the electron-injected current from one N electrode and the hole-injected current from the other N electrode, we derive a general formula for the differential conductance in a N/ d-wave S/N system under a Zeeman magnetic field on the d-wave S. It is found that oscillations of all quasiparticle transport coefficients and differential conductance with the bias voltage and the thickness of the d-wave S depend to a great extent on the crystal orientation of the d-wave S. In the N/ d-wave S/N junctions, the Zeeman magnetic field can lead to the Zeeman splitting of conductance peaks, and the temperature can reduce the coherent effect.