Dissipative quantum dynamics and error-correction with quantum acoustics
Abstract
Quantum systems experience errors, leading to an increase in their entropy. This entropy mustbe removed to allow them to function. In most approaches to error correction, this removal ofentropy is performed by the precise read-out of some property of the system, which informs usof the error which may have occurred. Typically, in an error correction protocol, this knowledgeof the error is then used to correct it by conditionally performing an operation that maps theerror states into the original error-free basis. For these measurement-based approaches to beeffective, the read-out step must be performed with extremely high fidelity. It must be followedvery rapidly by dynamics conditioned on its result. This doubly challenging requirement of highfidelityread-out & rapid feedback poses a significant technical challenge that has madeapproaching the break-even point of quantum error correction, for even a single logical qubit,extremely difficult.We propose an experimental research program to realize approaches for using dissipation,instead of measurement and feedback, to robustly engineer quantum states and correct errors.Focusing on quantum machines that use microwave circuits and motional degrees of freedom,our first goal is to demonstrate that engineered pulses can map errors from a logical qubit toancillary degrees of freedom where dissipation can be used to rapidly remove entropy andcorrect errors. In parallel, we will realize quantum acoustic systems consisting of a single qubitconnected to multiple mechanical oscillators. Inspired by related work in trapped ions andsuperconducting qubits, and leveraging our newly demonstrated quantum acoustic system thatoperates in the strong dispersive regime, we will use continuous-wave drives and dissipation tocool collections of mechanical oscillators into highly entangled states. Moreover, we willleverage the highly frequency-dependent responses that can be engineered in acoustic devicesto realize ``sinks for entropy that can be turned on and off with high contrast. In the final stageof our work, we will develop a hardware-efficient quantum acoustic approach to autonomousquantum error correction.Phonon-based approaches provide a natural substrate for implementing dissipation-basedapproaches to quantum state engineering and error correction. By bringing these fieldstogether, we expect to significantly push the state-of-the-art for hardware-efficient microwavequantum systems.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 17, 2020
- Source ID
- N000142012422
Entities
People
- Amir H. Safavi-Naeini
Organizations
- Office of Naval Research
- Stanford University
- United States Navy