Josephson Traveling Wave Parametric Amplifier as Quantum Source of Entangled Photons for Microwave Quantum Radar Applications

Josephson Traveling Wave Parametric Amplifier (JTWPA) has the potential to offer quantum limited noise and a large bandwidth. This amplifier is based on parametric amplification of microwaves traveling through a transmission line with embedded non-linear elements. In this paper, starting from the fabrication of the JTWPA, based on Quantum Electrodynamics (QEDs), operating as a non-classical quantum source for generating a signal-idler entangled state, its characterization in terms of scattering parameters is presented. The cryogenic and room temperature experimental results are discussed. The good performance of the JTWPA in terms of wide bandwidth and increased transmitted power makes it an ideal candidate for Microwave Quantum Radar (MQR) applications. Finally, the performance of an MQR based on the JTWPA developed at INRiM is reported, showing a radar maximum range equal to 82.2 m, which represents a greater value than previously published works.