1307.2431 (Bernd Braunecker et al.)

Interplay between classical magnetic moments and superconductivity in
quantum one-dimensional conductors: toward a self-sustained topological
Majorana phase    [PDF]

Bernd Braunecker, Pascal Simon

We study a one-dimensional (1D) interacting electronic liquid coupled to a 1D array of classical magnetic moments and to a superconductor. We show that at low energy and temperature the magnetic moments and the electrons become strongly entangled and that a magnetic spiral structure emerges without any adjustable parameters. For strong enough coupling between the two, the 1D electronic liquid is driven into a topological superconducting phase supporting Majorana fermions without any fine-tuning of external parameters. Our analysis applies at low enough temperature to a quantum wire in proximity of a superconductor when the hyperfine interaction between electrons and nuclear spins is taken into account or to a chain of magnetic adatoms adsorbed on a superconducting surface.

View original: http://arxiv.org/abs/1307.2431