Electrically detected interferometry of Majorana fermions in a topological insulator

Understand

We show how a chiral Dirac fermion (a massless electron or hole) can be converted into a pair of neutral chiral Majorana fermions (a particle equal to its own antiparticle).

• These two types of fermions exist on the metallic surface of a topological insulator, respectively, at a magnetic domain wall and at a magnet-superconductor interface.
• Interferometry of Majorana fermions is a key operation in topological quantum computation, but the detection is problematic since these particles have no charge.
• The Dirac-Majorana converter enables electrical detection of the interferometric signal.