Broadband and high compression power SNAIL parametric amplifier: part 2/2*

Resonator-based Josephson parametric amplifiers play a crucial role in superconducting quantum information processing. These amplifiers, such as the Josephson parametric amplifier (JPA) and the SNAIL parametric amplifier (SPA), are widely used due to their ease of operation and near quantum-limited noise performance. However, their limited compression power and bandwidth are not suitable for reading out multiple qubits simultaneously. Although amplifiers which have been optimized for either one of the desired metrics have been amply demonstrated, a single amplifier with significant improvement in both metrics is yet to be made available. In this talk, we present SNAIL parametric amplifiers (SPAs) with lumped element resonators fabricated by niobium tri-layer technology. In these devices, compression power is improved by using Josephson junctions with large critical current. Broader bandwidth is obtained by coupling the input signal to the device through a multi-pole filter. As a result, 10-fold improvements in compression power and bandwidth are achieved comparing to standard SPAs fabricated with single layer aluminum technology. 

 

In the first part of the talk, we will present the design principles of this amplifier. In the second part of the talk, we will present experimental results of this amplifier.