Digital feedback in superconducting quantum circuits

Abstract

This chapter covers the development of feedback control of superconducting qubits using projective measurement and a discrete set of conditional actions, here referred to as digital feedback. We begin with an overview of the applications of digital feedback in quantum computing. We then introduce an implementation of high-fidelity projective measurement of superconducting qubits. This development lays the ground for closed-loop control based on the binary measurement result. A first application of digital feedback control is fast and deterministic qubit reset, allowing the repeated initialization of a qubit more than an order of magnitude faster than its relaxation rate. A second application employs feedback in a multi-qubit setting to convert the generation of entanglement by parity measurement from probabilistic to deterministic, targeting an entangled state with the desired parity every time.

33 pages, 17 figures, chapter to appear in "Superconducting Devices in Quantum Optics"

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• Fast Scalable State Measurement with Superconducting Qubits
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Cited by in corpus (4)

• Basic protocols in quantum reinforcement learning with superconducting circuits
• Multiqubit and multilevel quantum reinforcement learning with quantum technologies
• Enhanced Quantum Synchronization via Quantum Machine Learning
• Scalable Self-Adaptive Synchronous Triggering System in Superconducting Quantum Computing