Identifying Majorana bound states by tunneling shot-noise tomography

Abstract

Majorana fermions are promising building blocks of forthcoming technology in quantum computing. However, their nonambiguous identification has remained a difficult issue because of the concomitant competition with other topologically trivial fermionic states, which poison their detection in most spectroscopic probes. By employing numerical and analytical methods, here we show that the Fano factor tomography is a key distinctive feature of a Majorana bound state, displaying a spatially constant Poissonian value equal to one. In contrast, the Fano factor of other trivial fermionic states, like the Yu-Shiba-Rusinov or Andreev ones, is strongly spatially dependent and exceeds one as a direct consequence of the local particle-hole symmetry breaking.