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arXiv · 2210.03763

Ab-initio tree-tensor-network digital twin for quantum computer benchmarking in 2D

Abstract

Large-scale numerical simulations of the Hamiltonian dynamics of a Noisy Intermediate Scale Quantum (NISQ) computer - a digital twin - could play a major role in developing efficient and scalable strategies for tuning quantum algorithms for specific hardware. Via a two-dimensional tensor network digital twin of a Rydberg atom quantum computer, we demonstrate the feasibility of such a program. In particular, we quantify the effects of gate crosstalks induced by the van der Waals interaction between Rydberg atoms: according to an 8$\times$8 digital twin simulation based on the current state-of-the-art experimental setups, the initial state of a five-qubit repetition code can be prepared with a high fidelity, a first indicator for a compatibility with fault-tolerant quantum computing. The preparation of a 64-qubit Greenberger-Horne-Zeilinger (GHZ) state with about 700 gates yields a $99.9\%$ fidelity in a closed system while achieving a speedup of $35\%$ via parallelization.

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Daniel Jaschke, Alice Pagano, Sebastian Weber, Simone Montangero. 2022-10-07. Ab-initio tree-tensor-network digital twin for quantum computer benchmarking in 2D. https://doi.org/10.1088/2058-9565%2Fad5585

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