TY - JOUR
T1 - Scalable simulation of nonequilibrium quantum dynamics via classically optimized unitary circuits
AU - Causer, Luke
AU - Jung, Felix
AU - Mitra, Asimpunya
AU - Pollmann, Frank
AU - Gammon-Smith, Adam
N1 - Publisher Copyright:
© 2024 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
PY - 2024/6
Y1 - 2024/6
N2 - The advent of near-term digital quantum computers could offer us an exciting opportunity to investigate quantum many-body phenomena beyond that of classical computing. To make the best use of the hardware available, it is paramount that we have methods that accurately simulate Hamiltonian dynamics for limited circuit depths. In this paper, we propose a method to classically optimize unitary brickwall circuits to approximate quantum time evolution operators. Our method is scalable in system size through the use of tensor networks. We demonstrate that, for various three-body Hamiltonians, our approach produces quantum circuits that can outperform trotterization in both their accuracy and the quantum circuit depth needed to implement the dynamics, with the exact details being dependent on the Hamiltonian. We also explain how to choose an optimal time step that minimizes the combined errors of the quantum device and the brickwall circuit approximation.
AB - The advent of near-term digital quantum computers could offer us an exciting opportunity to investigate quantum many-body phenomena beyond that of classical computing. To make the best use of the hardware available, it is paramount that we have methods that accurately simulate Hamiltonian dynamics for limited circuit depths. In this paper, we propose a method to classically optimize unitary brickwall circuits to approximate quantum time evolution operators. Our method is scalable in system size through the use of tensor networks. We demonstrate that, for various three-body Hamiltonians, our approach produces quantum circuits that can outperform trotterization in both their accuracy and the quantum circuit depth needed to implement the dynamics, with the exact details being dependent on the Hamiltonian. We also explain how to choose an optimal time step that minimizes the combined errors of the quantum device and the brickwall circuit approximation.
UR - http://www.scopus.com/inward/record.url?scp=85198749659&partnerID=8YFLogxK
U2 - 10.1103/PhysRevResearch.6.033062
DO - 10.1103/PhysRevResearch.6.033062
M3 - Article
AN - SCOPUS:85198749659
SN - 2643-1564
VL - 6
JO - Physical Review Research
JF - Physical Review Research
IS - 3
M1 - 033062
ER -