A high kinetic inductance-based single microwave photon detector – KIMIDET

In recent years, high kinetic inductance superconducting materials (HKIM) have gained a lot of interest in quantum circuit technologies. Operated in the microwave frequency domain they allow to engineer high impedance circuits providing an efficient way to e.g. increase the coherence time of superconducting quantum bits or couple electron charge and spins to microwave photons. This research project proposes to extend the prominent role of high kinetic inductance superconducting materials in quantum technologies by building a high kinetic inductance-based single microwave photon detector. The detection principle will be based on the large coupling of a single tunnel junction to a microwave resonator enabled by the use of high kinetic inductance superconducting materials in the fabrication process. The developed material will consist in superconducting granular aluminum which is compatible with optical and e-beam lithography and has already shown attractive microwave properties. This situation allows to efficiently convert a microwave photon into a single charge with a quantum efficiency close to unity. The charge is then detected using standard electrometry techniques. Up-to-now, this type of device only exists for photons with frequencies in the optical domain. Extending such a fundamental quantum detector to the microwave domain will open many new possibilities in quantum optics and quantum information processing with microwave photons.