Southwest Quantum Information and Technology

Lyapunov control-inspired quantum algorithms for ground state preparation

Presenting Author: James Larsen, Sandia National Laboratories
Contributing Author(s): Matthew Grace, Andrew Baczewski, Alicia Magann

The Feedback-based Algorithm for Quantum OptimizatioN (FALQON) was recently proposed as a new strategy for performing combinatorial optimization on quantum computers. The key feature of this approach is that it does not require any classical optimization, which differentiates it from QAOA and other variational quantum algorithms. Instead, quantum circuit parameter values are set using a deterministic feedback law derived from quantum Lyapunov control principles. This feedback law guarantees a monotonic improvement in solution quality with respect to the depth of the quantum circuit. In this poster, we explore how this framework can be adapted to applications beyond combinatorial optimization. To this end, we introduce a generalized formulation of feedback-based quantum algorithms for preparing ground states of quantum systems in a manner that is optimization-free. A variety of numerical analyses will be presented that investigate its performance for finding ground states of the Fermi-Hubbard model for strongly correlated quantum systems. Sandia National Labs is managed and operated by NTESS under DOE NNSA contract DENA0003525. SAND2022-10728 A.

(Session 5 : Thursday from 5:00 pm - 7:00 pm)