Enhanced zero-bias Majorana peak in disordered multi-subband quantum wires

Understand

A recent experiment [Mourik et al., Science 336, 1003 (2012)] on InSb quantum wires provides possible evidence for the realization of a topological superconducting phase and the formation of Majorana bound states.

• Motivated by this experiment, we consider the signature of Majorana bound states in the differential tunneling conductance of multi-subband wires.
• We show that the weight of the Majorana-induced zero-bias peak is strongly enhanced by mixing of subbands, when disorder is added to the end of the quantum wire.
• We also consider how the topological phase transition is reflected in the gap structure of the current-voltage characteristic.