What are Majorana Fermions and where to find them?


  Yuval Oreg  
Weizmann Institute of Science, Rehovot Israel

Topological quantum computation provides an elegant way around decoherence, as one encodes quantum information in a nonlocal fashion that the environment finds difficult to corrupt. Zero energy Majorana Fermion states (Majorans for short) emerges as a key concept for a realization of nonlocal encoding. In this talk we will discuss what are Majoranas? What makes them nonlocal? and how one may create and manipulate them. In particular we will discuss recipes for driving semiconducting wires into a topological phase supporting Majoranas. In this setting Majoarans can be transported, created, and fused by applying locally tunable gates to the wire. More importantly, we will show that networks of such wires allow braiding of Majoranas fermions and that they exhibit non-Abelian statistics like vortices in a p+ip superconductor.