Devices for Quantum Computing Applications

Josephson parametric devices are indispensable tools in superconducting quantum computing where they amplify, squeeze or entangle microwave signals, convert frequencies and process signals. This project will explore the properties of both Josephson parametric amplifiers (JPAs) and Josephson parametric oscillators (JPOs). The research is a collaboration with the US Joint Quantum Institute and Swedish researchers, and is being led by Dr Waltraut Wustmann of the University of Otago and the Quantum Materials Centre at the University of Maryland, US. Dr Wustman says that in traditional Josephson parametric amplifiers (JPAs), appreciable amplifier gain occurs only over a limited frequency range. If a significant widening of the amplifier bandwidth can be demonstrated, the team anticipates widespread adoption in superconducting quantum computing. Reading a qubit is a fundamental operation in quantum computing. It translates quantum information into classical information. In Josephson parametric oscillators (JPOs), photons are condensed into a coherent state, improving qubit readout. Despite their potential, many quantum aspects of JPOs have not been well tested and this research will add to the understanding of qubit encoding.