Cooper pair splitting in diffusive magnetic SQUIDs

Abstract

We study Josephson junctions with weak links consisting of two parallel disordered arms with magnetic properties -- ferromagnetic, half-metallic or normal with magnetic impurities. In the case of long links, the Josephson effect is dominated by mesoscopic fluctuations. In this regime, the system realises a ${\phi }_0$ junction with sample-dependent ${\phi }_0$ and critical current. Cooper pair splitting between the two arms plays a major role and leads to $2{\Phi }_0$ periodicity of the current as a function of flux between the arms. We calculate the current and its flux and polarization dependence for the three types of magnetic links.

7 pages, 3 figures. Version identical to journal version. Results unchanged. Manuscript has been extended, some intermediate calculation steps added, Eqs. (12)-(14). Clarified the relation with Refs [23,24]. The applicability range of Eqs. (16),(17) has been corrected. Minor corrections throughout the text. Added references

References in corpus (9)

• A spin triplet supercurrent through the half-metallic ferromagnet CrO2
• Direct coupling between magnetism and superconducting current in Josephson Phi junction
• Evidence for crossed Andreev reflection in superconductor-ferromagnet hybrid structures
• Josephson ${\phi }_0$-junction in nanowire quantum dots
• Evidence for Triplet Superconductivity in a Superconductor-Ferromagnet Spin Valve
• Near-unity Cooper pair splitting efficiency
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Cited by in corpus (4)

• Electrically modulated SQUID with single Josephson junction coupled by a time-reversal breaking Weyl semimetal thin film
• Proximity effect in a ferromagnetic semiconductor with spin-orbit interactions
• Mesoscopic supercurrent fluctuations in diffusive magnetic Josephson junctions
• Cooper pair splitting in ballistic ferromagnetic SQUIDs