Charge transport in normal metal/image-wave superconductor junctions with Rashba type spin–orbit coupling

We study charge transport in normal metal/s+p-wave superconductor (S+P) junctions with Rashba type spin–orbit coupling (RSOC). Applying the Blonder–Tinkham–Klapwijk theory, we calculate a bias (V) dependence of tunneling conductance, changing the strength of RSOC and Δp/Δs. Here Δs(p) is the absolute value of pair potential of S(P) component. For Δp<Δs, a gap structure appears ranging from eV=0 to eV=|Δs-Δp|, and a coherent peak appears at eV=|Δs+Δp|. For Δp>Δs, a zero bias conductance peak (ZBCP) is formed, a dip structure appears at |Δs-Δp|, and a weak coherent peak appears at eV=|Δs+Δp|. For large RSOC, a weak peak appears at eV=|Δs-Δp| because of RSOC. The bias dependence of conductance depends on the ratio Δp/Δs and changes qualitatively at Δp/Δs=1. For Δp>Δs, |Δs-Δp| can be estimated from a width of ZBCP. For Δs>Δp, Δs and Δp can be estimated from the gap structure and the coherent peak. Thus, the magnitude of gaps can be determined from the experiment of scanning tunneling spectroscopy.