D.C. Josephson transport by quartets and other Andreev resonances in superconducting bijunctions

Régis Mélin (1) , Denis Feinberg (1) , Hervé Courtois (2) , Ciprian Padurariu (1) , Andreas Pfeffer (3) , Jean Eudes Duvauchelle (3) , Francois Lefloch (3) , Thibaut Jonckheere (4) , Jérôme Rech (5, 4) , Thierry Martin (4) , Benoît Douçot (6)

1 NEEL - ThQC - Théorie Quantique des Circuits
2 NEEL - QuNES - Nano-Electronique Quantique et Spectroscopie
3 LaTEQS - Laboratoire de Transport Electronique Quantique et Supraconductivité
4 CPT - Centre de Physique Théorique - UMR 7332
5 CPT - E6 Nanophysique
6 LPTHE - Laboratoire de Physique Théorique et Hautes Energies

Bijunctions are three-terminal Josephson junctions where three superconductors are connected by a single weak link made of a metallic region or of quantum dots. Biasing two of the superconductors with commensurate voltages yields Andreev resonances that produce d.c. Josephson currents made of correlated Cooper pairs. For instance with applied voltages (0, V, -V ), quartets formed by two entangled Cooper pairs are emitted by one reservoir towards the two others. Theory involving non-equilibrium Green's functions reveal the microsopic mechanism at play, e.g multiple coherent Andreev reflections that provide an energy-conserving and fully coherent channel. Recent experiments on dffusive Aluminum-Copper bijunctions show transport anomalies that are interpreted in terms of quartet resonances.

Mots clés: Nonlocal transport; Josephson Junctions

Domaines: Systèmes mésoscopiques et effet Hall quantique [cond-mat.mes-hall]

Régis Mélin, Denis Feinberg, Hervé Courtois, Ciprian Padurariu, Andreas Pfeffer, et al.. D.C. Josephson transport by quartets and other Andreev resonances in superconducting bijunctions. Journal of Physics: Conference Series, 2014, 568 (5), pp.052006. ⟨10.1088/1742-6596/568/5/052006⟩. ⟨hal-01057351⟩