Tunneling spectroscopy between a ferromagnet and s-wave superconductor carrying a supercurrent

The Bogoliubov-de Gennes equation and Blonder-Tinkham-Klapwijk model are applied to studying tunneling spectroscopy between a ferromagnet and s-wave superconductor carrying a supercurrent in the clean limit. It is found that a three peak structure including a peak at zero energy at nearly critical IS and Z≈0.5 appears because the system has become gapless for both normal metal/superconductor (N/S) and ferromagnet/superconductor (F/S) junctions. In the presence of exchange energy, besides the gaplessness on the Fermi surface, the other interesting result is that the coherence peaks are split into two peaks respectively due to the presence of the transverse supercurrent in S, and the coherence peaks splitting becomes large with increasing the supercurrent.