1202.1018 (Jian Li et al.)

Scattering theory of chiral Majorana fermion interferometry    [PDF]

Jian Li, Geneviève Fleury, Markus Büttiker

Using scattering theory, we investigate interferometers composed of chiral
Majorana fermion modes coupled to normal metal leads. We advance an approach in
which also the basis states in the normal leads are written in terms of
Majorana modes. Thus each pair of electron-hole states is associated with a
pair of Majorana modes. Only one lead Majorana mode couples to the intrinsic
Majorana mode whereas its partner is completely reflected. Similarly the
remaining Majorana modes are completely reflected but in general mix pair-wise.
We demonstrate that the charge current can also be expressed in terms of
interference between pairs of Majorana modes. These two basic facts permit a
treatment and understanding of current and noise signatures of chiral Majorana
fermion interferometry in an especially elegant way. As a particular example of
applications, in Fabry-Perot-type interferometers where chiral Majorana modes
form loops, resonances (anti-resonances) from such loops always lead to peaked
(suppressed) Andreev differential conductances, and negative (positive)
cross-correlations that originate purely from two-Majorana-fermion exchange.
These investigations are intimately related to current and noise signatures of
Majorana bound states.

View original: http://arxiv.org/abs/1202.1018