English

Unpaired Majorana fermions in quantum wires

Mesoscale and Nanoscale Physics 2009-10-31 v2 Quantum Physics

Abstract

Certain one-dimensional Fermi systems have an energy gap in the bulk spectrum while boundary states are described by one Majorana operator per boundary point. A finite system of length LL possesses two ground states with an energy difference proportional to exp(L/l0)\exp(-L/l_0) and different fermionic parities. Such systems can be used as qubits since they are intrinsically immune to decoherence. The property of a system to have boundary Majorana fermions is expressed as a condition on the bulk electron spectrum. The condition is satisfied in the presence of an arbitrary small energy gap induced by proximity of a 3-dimensional p-wave superconductor, provided that the normal spectrum has an odd number of Fermi points in each half of the Brillouin zone (each spin component counts separately).

Keywords

Cite

@article{arxiv.cond-mat/0010440,
  title  = {Unpaired Majorana fermions in quantum wires},
  author = {Alexei Kitaev},
  journal= {arXiv preprint arXiv:cond-mat/0010440},
  year   = {2009}
}

Comments

16 pages, 5 figures, Latex and epsf, to be included in the proceedings of the Mesoscopic And Strongly Correlated Electron Systems conference (9-16 July 2000, Chernogolovka, Moscow Region, Russia), one reference added