Spin-sensitive long-range proximity effect in ferromagnet/spin-triplet-superconductor bilayers

Abstract

The discovery of noncentrosymmetric superconductors, such as CePt3Si, and chiral superconductors, such as Sr2RuO4, calls for experimental methods to identify the presence of spin-triplet pairing. We here demonstrate a method which accomplishes this in an appealingly simple manner: a spin-sensitive proximity effect in a ferromagnet/triplet superconductor bilayer. It is shown how the orientation of the field can be used to unambiguously distinguish between different spin-triplet states. Moreover, the proximity effect becomes long ranged in spite of the presence of an exchange field and even without any magnetic inhomogeneities, in contrast to conventional S/F junctions. Our results can be verified by scanning-tunneling-microscopy spectroscopy and can be useful as a tool to characterize the pairing state in unconventional superconducting materials. ©2011 American Physical Society