Linnaeus Colloquium: Topological trouble: The problem with braiding Majoranas

​Colloquium by David DiVincenzo, RWTH Aachen, Germany

I will begin with a general discussion of anyons, of which Majoranas are an example.  I continue with a discussion of why particle statistics in 2D can be neither bosonic nor fermionic, nor even abelian, and what it
means for the charge to be fractional.  A simple model of Kitaev, of electrons hopping on a branched 1D lattice with strong spin-orbit coupling and superconducting pairing, is sufficient to describe Majoranas and the gates that can be done by moving them around each other (braiding).  I discuss a model calculation of the decohence of these Majorana qubits during braiding in a trijunction, due to thermally generated quasiparticles (bosonic environment).  The limitations to coherence are significant; topological protection doesn't really work in this scenario.  (work with Dr. Fabio Pedrocchi)

​Coffee and cake will be served 15 min. before the start of the seminar
Category Colloquium
Location: Kollektorn, lecture room, MC2-huset, MC2
Starts: 07 December, 2017, 15:15
Ends: 07 December, 2017, 16:00

Published: Fri 25 Aug 2017. Modified: Thu 30 Nov 2017