Travelling Wave Parametric Amplifiers At Utility Scale

At IBM Quantum we have iterated over multiple generations of 100+ qubit systems (Eagle, Osprey, Heron, Crossbill, Nighthawk) with a continued focus on building larger systems. As part of this effort our readout hardware has evolved to meet both scaling requirements and performance requirements to build out these systems. One aspect of this evolution is how we design, package and place traveling wave parametric amplifiers (TWPA's) in our readout chain. At the device design level, we look to improve loss and suppress unwanted parametric processes as both have down stream impacts on system dynamic efficiency. These design considerations include adjusting the capacitor layout, resonator layout and the dispersion profile of the TWPA. At the system integration level, we look to tightly integrate other passive microwave components required for TWPA operation. For example, placing filters in an integrated package to impedance match across signal and idler bands and minimize insertion loss. This approach allows us to improve gain and efficiency realizing more performant amplification in our readout chain.