2011/08/01 by T. -P. Choy, J. M. Edge, A. R. Akhmerov +1 · 3 citations
Physics and Astronomy · #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.84.195442
published as Phys. Rev. B 84, 195442 (2011) · 7 pages, 5 figures
arxiv created 2011/08/01 · arxiv updated 2011/11/10
There exists a variety of proposals to transform a conventional s-wave superconductor into a topological superconductor, supporting Majorana fermion mid-gap states. A necessary ingredient of these proposals is strong spin-orbit coupling. Here we propose an alternative system consisting of a one-dimensional chain of magnetic nanoparticles on a superconducting substrate. No spin-orbit coupling in the superconductor is needed. We calculate the topological quantum number of a chain of finite length, including the competing effects of disorder in the orientation of the magnetic moments and in the hopping energies, to identify the transition into the topologically nontrivial state (with Majorana fermions at the end points of the chain).