45
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Controllable 0-pi Josephson junctions containing a ferromagnetic spin valve

      Preprint

      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Superconductivity and ferromagnetism are antagonistic forms of order, and rarely coexist. Many interesting new phenomena occur, however, in hybrid superconducting/ferromagnetic systems. For example, a Josephson junction containing a ferromagnetic material can exhibit an intrinsic phase shift of pi in its ground state for certain thicknesses of the material. Such "pi-junctions" were first realized experimentally in 2001, and have been proposed as circuit elements for both high-speed classical superconducting computing and for quantum computing. Here we demonstrate experimentally that the phase state of a Josephson junction containing two ferromagnetic layers can be toggled between 0 and pi by changing the relative orientation of the two magnetizations. These controllable 0-pi junctions have immediate applications in cryogenic memory where they serve as a necessary component to an ultra-low power superconducting computer. Such a fully superconducting computer is estimated to be orders of magnitude more energy-efficient than current semiconductor-based supercomputers. Phase controllable junctions also open up new possibilities for superconducting circuit elements such as superconducting "programmable logic," where they could function in superconducting analogs to field-programmable gate arrays.

          Related collections

          Author and article information

          Journal
          10.1038/nphys3681
          1509.05368
          http://arxiv.org/licenses/nonexclusive-distrib/1.0/

          Condensed matter
          Condensed matter

          Comments

          Comment on this article