Observation of zero-bias conductance peak in topologically-trivial hybrid superconducting interfaces

Abstract

Proximity effects between s-wave superconducting thin films and high spin-orbit topological materials are widely studied using the differential conductance spectroscopy technique, mainly to investigate the topological property of the induced superconductivity. However, very little is probed about the influence of above proximity effect on the depairing properties of the proximitized superconducting film. Here, we provide a phenomenological simulation tool to characterize the different pair-breaking mechanisms that exist at such interfaces and show how they affect the differential tunneling conductance response in applied magnetic fields. Importantly, we probe the quasiparticle-tunneling conductance at the hybrid interface and observe conductance peak pinning at zero bias in a larger field range with eventual signs of weak peak splitting. Further, the effect of varying the spin-orbit scattering and the Landé g-factor in tuning the conductance peaks show interesting trends, such as observation of zero bias conductance peak even in a topologically-trivial superconducting state.

Evolution of 4π-Periodic Supercurrent in the Presence of an In-Plane Magnetic Field

“…Josephson junctions (JJs) fabricated on semiconductor structures with epitaxially grown superconductors have recently attracted attention due to their propitious characteristics − and applications in quantum computing. − In the presence of a Zeeman field − or a phase bias − and a strong spin–orbit coupling (SOC) interaction, such high-quality JJs have shown signatures of topological superconductivity, − which can host Majorana zero modes useful for fault-tolerant quantum computation. , However, robust implementation and signatures of topological superconductivity remain ambiguous. − …”