Lossless resilient microwave components based on disordered superconductors – HARDWAVE

Aside from quantum processors, superconducting quantum circuits have brought numerous developments in lossless microwave components. A notorious example is the demonstration of superconducting quantum limited amplifiers (QLA’s), resonant or traveling wave, which became an essential microwave component of state-of-the-art amplification chains. Other on-chip microwave components such as tunable coupler, tunable resonator, and high frequency circulator allowed crucial lossless treatment of quantum signals.
However, most of these microwave components are based on the superconducting phase non-linearity provided by Josephson junctions (JJ’s). Yet, as a consequence of being built upon aluminum JJ’s, all of these components are restricted to low magnetic field ?250mT, temperature ?250mK and frequency ?10GHz to work properly. These constraints prevent the spread of lossless microwave components to other research fields such as semiconductor spin-qubits (magnetic field ~1T) and spatial photon detectors (temperature ~1K and frequency ~100GHz).
The project ambitious goal is to demonstrate that the non-linearity of large gap disordered superconductors, here NbN, can advantageously replace Al JJ's and offer lossless microwave components to research community working at large magnetic field ~6T, temperature ~4K and frequency ~100GHz.
According to the project's tight time frame, we will concentrate here on building one specific non-linear lossless microwave component, a Kinetic Traveling Wave Parametric Amplifier (KTWPA), and demonstrate its resilience against magnetic field.
Once our KTWPA is fully characterize and meets our large magnetic field resilience constraints, we will use it to demonstrate, in collaboration with R. MAURAND, fast Quantum Non Demolition (QND) single shot readout of a single hole-spin.