Towards strong evidence of Majorana bound state by a combined measurement of tunneling conductance and current noise

Abstract

Recently, hunting-Majorana community has reported the experimental observations of nearly quantized conductance plateau and integer Fano factor: both phenomena were believed as exclusive hallmarks of Majorana bound state. Within a unified theoretical framework, we show that zeroenergy Andreev bound states can also generate both a nearly quantized conductance plateau, and an integer Fano factor, in a sizable, continuous, yet topologically trivial parameter space. Importantly, we further propose to obtain strong Majorana evidence by a combined measurement of tunneling conductance and current noise. Specifically, for a Majorana bound state and zero-energy Andreev bound state, a nearly quantized zero-bias conductance peak always accompanies a zero-bias dip and peak, respectively, of the differential current noise. This protocol, designed for the simplest two-terminal device, can be practically implemented in multiple MBS candidate platforms.

Majorana differential shot noise and its universal thermoelectric crossover

“…In particular, in Ref. [79] it is demonstrated that in presence of MBSs a dip of the differential shot noise is always accompanied by a peak of the differential conductance. This behavior has also been observed earlier in Ref.…”