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arXiv · 2202.09372

Quantum Optimization of Maximum Independent Set using Rydberg Atom Arrays

Abstract

Realizing quantum speedup for practically relevant, computationally hard problems is a central challenge in quantum information science. Using Rydberg atom arrays with up to 289 qubits in two spatial dimensions, we experimentally investigate quantum algorithms for solving the Maximum Independent Set problem. We use a hardware-efficient encoding associated with Rydberg blockade, realize closed-loop optimization to test several variational algorithms, and subsequently apply them to systematically explore a class of graphs with programmable connectivity. We find the problem hardness is controlled by the solution degeneracy and number of local minima, and experimentally benchmark the quantum algorithm's performance against classical simulated annealing. On the hardest graphs, we observe a superlinear quantum speedup in finding exact solutions in the deep circuit regime and analyze its origins.

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Sepehr Ebadi, Alexander Keesling, Madelyn Cain, Tout T. Wang, Harry Levine, Dolev Bluvstein, Giulia Semeghini, Ahmed Omran, Jinguo Liu, Rhine Samajdar, Xiu-Zhe Luo, Beatrice Nash, Xun Gao, Boaz Barak, Edward Farhi, Subir Sachdev, Nathan Gemelke, Leo Zhou, Soonwon Choi, Hannes Pichler, Shengtao Wang, Markus Greiner, Vladan Vuletic, Mikhail D. Lukin. 2022-02-18. Quantum Optimization of Maximum Independent Set using Rydberg Atom Arrays. https://doi.org/10.1126/science.abo6587

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