Robust Measurements of $n$ -Point Correlation Functions of Driven-Dissipative Quantum Systems on a Digital Quantum Computer

Journal Article · 03 March 2024 · Physical Review Letters

DOI: https://doi.org/10.1103/PhysRevLett.132.100601 · OSTI ID:2318605

Del Re, Lorenzo ; Rost, Brian ; Foss-Feig, Michael; Kemper, A. F. ; Freericks, J. K.

We propose and demonstrate a unified hierarchical method to measure $n$ -point correlation functions that can be applied to driven, dissipative, or otherwise open or nonequilibrium quantum systems. In this method, the time evolution of the system is repeatedly interrupted by interacting an ancilla qubit with the system through a controlled operation, and measuring the ancilla immediately afterward. We discuss the robustness of this method as compared to other ancilla-based interferometric techniques (such as the Hadamard test), and highlight its advantages for near-term quantum simulations of open quantum systems. We implement the method on a quantum computer in order to measure single-particle Green’s functions of a driven-dissipative fermionic system. This Letter shows that dynamical correlation functions for driven-dissipative systems can be robustly measured with near-term quantum computers. Published by the American Physical Society 2024

• Research Organization: North Carolina State University, Raleigh, NC (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division (MSE)
• Grant/Contract Number: SC0019469; SC0023231
• OSTI ID: 2318605
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 10 Vol. 132; ISSN 0031-9007; ISSN PRLTAO
• Publisher: American Physical SocietyCopyright Statement
• Country of Publication: United States
• Language: English