Local Andreev reflection induced by Chiral Majorana Fermions

When superconductivity is proximity induced into a quantum anomalous system, it is predicted to host Chiral Majorana Edge Modes(CMEMs), which would induce a unique half quantized plateau as its transport signature. This was recently found in the experiments[Science 357, 294 (2017)]. However, it was argued that without superconductivity, disorder alone could also induce such signature. Thus more experimental evidence is called to determine whether superconductivity was the actual factor. Here we proposed to use local tunneling spectroscopy to directly probe the edge state of the hybrid system. We used Non-Equilibrium Green's Function to show that for topological phase with chern number N=±1/2 which hosts 1/2 CMEM would have a dip/plateau in differential conductance measurements respectively. Comparison with Thermal metal was also included.