Precise patterning of graphene for voltage-tunable Josephson Junctions*

Gate-tunable Josephson junctions provide a promising platform to engineer novel elemental components of superconducting circuits. Particularly, graphene-based weak-link Josephson junctions offer the advantage that the critical current can be easily tuned by the gate voltage. Modifying the dimensions of the graphene can offer another control knob to achieve the desired critical currents. This is important for applications such as gatemons (gate-tunable Josephson junction-based qubits), which have emerged as an alternative approach to mitigate some of the key challenges in superconducting qubits [1]. Here, we explore the use of local anodic oxidation based on atomic force microscopy [2] as part of a clean fabrication process of graphene junctions with a geometry controllable at the submicron scale.

[1] Wang*, Rodan-Legrain* et al. Nat. Nanotech.  (2019)

[2] Li, et al. Nano Letters (2018)