Long-range Cooper pair splitting by chiral Majorana edge states

Abstract

We analyze the transport properties of a Cooper pair splitter device made up of two-point electrodes in contact with a ferromagnetic/superconductor (F/S) junction built on the surface of a topological insulator. For the pair potential of the S region we consider s-and d-wave symmetries, and for the F region, we regard a magnetization vector normal to the TI surface. The non-local transport along the F/S interface is mediated by chiral Majorana edge states, with chirality controlled by the magnetization vector polarization. We show that the crossed Andreev reflection amplitude slowly decays with the separation of the electrodes for standard clean samples. Our system would reach a maximum Cooper pair-splitting efficiency of 80% for a symmetrical voltage configuration, even in high-temperature superconductors devices.