Readout Chains for Transmon Qubits in Production Scaled Quantum Computers

Superconducting circuits have emerged as a leading commercial platform for quantum computing, spurred by continued and rapid advances in qubit quality, processor speed, and system scale. The realization of large-scale superconducting processors, such as IBM’s 433 qubit Osprey system, has been enabled, in part, by technologies developed over the past two decades to efficiently extract femtowatt-level signals from cryogenic environments. In this talk I will provide an overview of dispersive readout with superconducting qubits, highlighting critical sub-components such as multiplexed qubit readout and Josephson parametric amplifiers. I will also provide a perspective on readout-related challenges as we scale to thousands of qubits, emphasizing engineering tradeoffs prompted by modular system architectures.