22 Jul 2024 | Natasha Sachdeva, Gavin S. Hartnett, Smarak Maity, Samuel Marsh, Yulun Wang, Adam Winick, Ryan Dougherty, Daniel Canuto, You Quan Chong, Michael Hush, Pranav S. Mundada, Christopher D. B. Bentley, Michael J. Biercuk, and Yuval Baum
The paper introduces a comprehensive quantum solver for binary combinatorial optimization problems on gate-model quantum computers, which outperforms existing alternatives and consistently delivers correct solutions for problems with up to 127 qubits. The solver includes a customized ansatz, efficient error suppression, and overhead-free post-processing to correct bit-flip errors. Benchmarking on IBM quantum computers, the solver successfully solves Max-Cut instances for random regular graphs with up to 120 qubits, demonstrating a 4× increase in problem size compared to previous trapped-ion quantum computer implementations and a 9× increase in the likelihood of finding the correct solution. For higher-order binary optimization, the solver successfully searches for the ground state energy of a 127-qubit spin-glass model, increasing the likelihood of finding the minimum energy by up to 1,500× compared to published results using a D-Wave annealer. The solver also outperforms a heuristic local solver for both problem types. These results represent the largest quantum optimizations successfully solved on hardware to date and demonstrate the first time a gate-model quantum computer has outperformed a quantum annealer for binary optimization problems.The paper introduces a comprehensive quantum solver for binary combinatorial optimization problems on gate-model quantum computers, which outperforms existing alternatives and consistently delivers correct solutions for problems with up to 127 qubits. The solver includes a customized ansatz, efficient error suppression, and overhead-free post-processing to correct bit-flip errors. Benchmarking on IBM quantum computers, the solver successfully solves Max-Cut instances for random regular graphs with up to 120 qubits, demonstrating a 4× increase in problem size compared to previous trapped-ion quantum computer implementations and a 9× increase in the likelihood of finding the correct solution. For higher-order binary optimization, the solver successfully searches for the ground state energy of a 127-qubit spin-glass model, increasing the likelihood of finding the minimum energy by up to 1,500× compared to published results using a D-Wave annealer. The solver also outperforms a heuristic local solver for both problem types. These results represent the largest quantum optimizations successfully solved on hardware to date and demonstrate the first time a gate-model quantum computer has outperformed a quantum annealer for binary optimization problems.