Topological qubits based on quantum Hall Josephson junctions offer a promising route toward robust quantum computing, but a key challenge remains: how to read out their quantum states in a controlled and scalable way. In my PhD project, I aim to address this by developing a graphene-based quantum Hall Josephson junction that is strongly coupled to a superconducting microwave resonator, enabling spectroscopic access to Andreev bound states.

Previous work in our group has demonstrated an h/e-periodic supercurrent in graphene Josephson junctions at filling factor nu=2, highlighting their potential for topological applications. Building on this, my work focuses on integrating such systems with resonators to allow standard microwave readout techniques—similar to those used in superconducting qubits. Achieving this is particularly challenging due to the high magnetic fields required for the quantum Hall regime, which are typically incompatible with conventional superconducting circuits. To overcome this, I am exploring the use of high-Hc2 superconducting resonators, galvanically coupled to the junction, to enable strong coupling and robust operation in these extreme conditions.