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arXiv · 2412.18007

Entropy density benchmarking of near-term quantum circuits

Marine Demarty·James Mills·Kenza Hammam·Raul Garcia-Patron
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Abstract

Understanding the limitations imposed by noise on current and next-generation quantum devices is a crucial step toward demonstrating practical quantum advantage. In this work, we investigate the accumulation of entropy density as a benchmark to monitor the performance of quantum processing units (QPUs). We provide a proof-of-principle demonstration of our methodology which entails developing simple heuristic models of how entropy accumulates, testing them against real QPU data, and finally using these models to determine a circuit volume threshold above which quantum advantage is unattainable. Monitoring entropy density not only offers an alternative approach that complements existing circuit-level benchmarking techniques, but, more importantly, it bridges the gap between circuit-level and application-level benchmarking protocols. In particular, our heuristic model of entropy accumulation allows us to outperform existing techniques that bound the circuit-size threshold for quantum advantage.

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Marine Demarty, James Mills, Kenza Hammam, Raul Garcia-Patron. 2024-12-23. Entropy density benchmarking of near-term quantum circuits. https://doi.org/10.1103/swvt-3pkh

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