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arXiv · 0711.4955

Josephson current and Andreev states in superconductor-half metal-superconductor heterostructures

Artem V. Galaktionov·Mikhail S. Kalenkov·Andrei D. Zaikin
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Abstract

We develop a detailed microscopic theory describing dc Josephson effect and Andreev bound states in superconducting junctions with a half-metal. In such systems the supercurrent is caused by triplet pairing states emerging due to spin-flip scattering at the interfaces between superconducting electrodes and the half-metal. For sufficiently clean metals we provide a detailed non-perturbative description of the Josephson current at arbitrary transmissions and spin-flip scattering parameters for both interfaces. Our analysis demonstrates that the behavior of both the Josephson current and Andreev bound states crucially depends on the strength of spin-flip scattering showing a rich variety of features which can be tested in future experiments.

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Artem V. Galaktionov, Mikhail S. Kalenkov, Andrei D. Zaikin. 2008-03-28. Josephson current and Andreev states in superconductor-half metal-superconductor heterostructures. https://doi.org/10.1103/physrevb.77.094520

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