Grid-based methods for chemistry simulations on a quantum computer

Journal article

First-quantized, grid-based methods for chemistry modeling are a natural and elegant fit for quantum computers. However, it is infeasible to use today’s quantum prototypes to explore the power of this approach because it requires a substantial number of near-perfect qubits. Here, we use exactly emulated quantum computers with up to 36 qubits to execute deep yet resource-frugal algorithms that model 2D and 3D atoms with single and paired particles. A range of tasks is explored, from ground state preparation and energy estimation to the dynamics of scattering and ionization; we evaluate various methods within the split-operator QFT (SO-QFT) Hamiltonian simulation paradigm, including protocols previously described in theoretical papers and our own techniques. While we identify certain restrictions and caveats, generally, the grid-based method is found to perform very well; our results are consistent with the view that first-quantized paradigms will be dominant from the early fault-tolerant quantum computing era onward.

Authors: Chan, HHS; Meister, R; Jones, T; Tew, DP; Benjamin, SC

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Association for the Advancement of Science
• Journal: Science Advances
• Volume: 9
• Issue: 9
• Article number: eabo7484
• Publication date: 2023-03-01
• Acceptance date: 2023-01-30
• DOI: 10.1126/sciadv.abo7484
• EISSN: 2375-2548
• Language: English
• Keywords: FFR