Three-wave mixing Josephson traveling wave parametric amplifiers at 750 MHz and 1500 MHz

We present our latest results on Josephson traveling wave parametric amplifiers (TWPAs), which are currently in fabrication with our Nb/Al-AlO_x/Nb junction process. As a follow-up of our successful 4-9 GHz demonstrator operating in three-wave mixing, we are pursuing the adaptation of the TWPA concept to lower radio frequency bands. The motivation is to extend the application area to, e.g., spin qubit quantum computing. The device design features superconducting nonlinear asymmetric inductive elements (SNAILs), and an integrated on-chip magnetic flux bias line. We will discuss how we approach some specific low-frequency challenges such as control over footprint and engineered dispersion.