Full electrostatic control of quantum interference in an extended trenched Josephson junction

Stefano Guiducci (1) , Matteo Carrega (1) , Fabio Taddei (1) , Giorgio Biasiol (2) , Hervé Courtois (3) , Fabio Beltram (1) , Stefan Heun (1)

1 NEST - National Enterprise for nanoScience and nanoTechnology
2 IOM - CNR Istituto Officina dei Materiali
3 NEEL - QuNES - Nano-Electronique Quantique et Spectroscopie

Hybrid semiconductor/superconductor devices constitute an important platform for a wide range of applications, from quantum computing to topological-state-based architectures. Here, we demonstrate full modulation of the interference pattern in a superconducting interference device with two parallel islands of ballistic InAs quantum wells separated by a trench, by acting independently on two side-gates. This so far unexplored geometry enables us to tune the device with high precision from a SQUID-like to a Fraunhofer-like behavior simply by electrostatic gating, without the need for an additional in-plane magnetic field. These measurements are successfully analyzed within a theoretical model of an extended tunnel Josephson junction, taking into account the focusing factor of the setup. The impact of these results on the design of novel devices is discussed.

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

Stefano Guiducci, Matteo Carrega, Fabio Taddei, Giorgio Biasiol, Hervé Courtois, et al.. Full electrostatic control of quantum interference in an extended trenched Josephson junction. Physical Review B, 2019, 99 (23), pp.235419. ⟨10.1103/PhysRevB.99.235419⟩. ⟨hal-02090456⟩