Critical slowing down in circuit quantum electrodynamics

Journal article

Critical slowing down of the time it takes a system to reach equilibrium is a key signature of bistability in dissipative first-order phase transitions. Understanding and characterizing this process can shed light on the underlying many-body dynamics that occur close to such a transition. Here, we explore the rich quantum activation dynamics and the appearance of critical slowing down in an engineered superconducting quantum circuit. Specifically, we investigate the intermediate bistable regime of the generalized Jaynes-Cummings Hamiltonian (GJC), realized by a circuit quantum electrodynamics (cQED) system consisting of a transmon qubit coupled to a microwave cavity. We find a previously unidentified regime of quantum activation in which the critical slowing down reaches saturation and, by comparing our experimental results with a range of models, we shed light on the fundamental role played by the qubit in this regime.

Authors: Brookes, P; Tancredi, G; Patterson, AD; Rahamim, J; Esposito, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Association for the Advancement of Science
• Journal: Science Advances
• Volume: 7
• Issue: 21
• Article number: eabe9492
• Publication date: 2021-05-19
• Acceptance date: 2021-03-29
• DOI: 10.1126/sciadv.abe9492
• EISSN: 2375-2548
• Pmid: 34138743
• Language: English
• Keywords: FFR