Time/Venue Monday, January 13 at 2 pm in Old LeConte 325
Host Ehud Altman
Title The Measurement-Induced Transition in Open Quantum Systems
Abstract Quantum technologies fundamentally rely on quantum control, measurement, and feedback. Measurement-induced transitions are a recently uncovered class of critical phenomena that occur when many-body unitary dynamics are interspersed with measurements at a tunable rate [1,2]. We uncover precise connections between this phase transition and quantum error correction thresholds in the quantum channel capacity of open system dynamics [3,4]. We then show how to define a local order parameter for the transition that measures the ability of the system to store one bit of quantum information for exponentially long times . Using this order parameter, we identify scalable probes of the transition that are immediately applicable to advanced quantum computing platforms such as trapped ions or superconducting qubits. Studying this class of measurement-driven many-body dynamics may potentially lead to more efficient realizations of scalable, fault-tolerant quantum computing, as well as deepen our understanding of the transition from quantum to classical physics in many-body systems.
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