Parametric amplifier development and single-shot readout of superconducting qubits - Josh Mutus

Designing amplifiers for use in a scalable, fault-tolerant quantum computer presents a host of challenges. Fault-tolerant schemes, such as the surface code, require fast, high-fidelity readout of multiple qubits. We have developed lumped-element parametric amplifiers for reading out superconducting qubits with this direction in mind. Built using wafer-scale, multi-layer fabrication techniques these single-ended parametric amplifiers allow for wider bandwidth and higher saturation performance. Additionally, our amplifiers allow for flexible operation using multiple pump modes; they operate at the quantum limit for gains exceeding 30 dB and a gain-bandwidth product greater than 500 MHz. These amplifiers are capable of 99% single-shot readout fidelity on our superconducting qubits.