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arXiv · 1711.02687

Measurement-driven quantum computing: Performance of a 3-SAT solver

Simon C. Benjamin·Liming Zhao·Joseph F. Fitzsimons
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Abstract

We investigate the performance of a quantum algorithm for solving classical 3-SAT problems. A cycle of post-selected measurements drives the computer's register monotonically toward a steady state which is correlated to the classical solution(s). An internal parameter $\theta$ determines both the degree of correlation and the success probability, thus controlling the algorithm's runtime. Optionally this parameter can be gradually evolved during the algorithm's execution to create a Zeno-like effect; this can be viewed as an adiabatic evolution of a Hamiltonian which remains frustration-free at all points, and we lower-bound the corresponding gap. In exact numerical simulations of small systems up to 34 qubits our approach competes favourably with a high-performing classical 3-SAT solver, which itself outperforms a brute-force application of Grover's search.

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Simon C. Benjamin, Liming Zhao, Joseph F. Fitzsimons. 2017-11-07. Measurement-driven quantum computing: Performance of a 3-SAT solver. https://arxiv.org/abs/1711.02687

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