Quantized zero bias conductance plateaus in hybrid nanowire topological quantum information processing platforms without non-Abelian Majorana zero modes*

Braiding operations in topological quantum computations inherently rely on the spatial separation between Majorana bound states (MBSs), as a result a method of distinguishing between these quasi-Majorana states and true Majorana zero modes (MZMs), localized at the ends of a semiconductor-superconductor (SM-SC) nanowire, is essential in the creation of a topological quantum bit. Here we show that recently observed, 2e^2/h-quantized zero-bias conductance plateaus, may arise in SM-SC nanowires due to the presence of quasi-Majorana states, for which the constituent MBSs are specially separated on the order of the Majorana decay length. Because these quasi-Majoranas form rather generically within the topologically trivial regime, our results establish that the observation of 2e^2/h-quantized zero-bias conductance plateaus does not represent sufficient evidence of the existence of non-Abelian MZMs localized at the opposite ends of a wire. Thus, we conclude that localized charge tunneling measurements, so far considered the primary probe for the existence of MZMs, have exhausted their potential to reveal useful information in distinguishing MZMs from low energy Andreev bound states within SM-SC hybrid structures.