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arXiv · 2011.02621

Verifying Random Quantum Circuits with Arbitrary Geometry Using Tensor Network States Algorithm

Chu Guo·Youwei Zhao·He-Liang Huang
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Abstract

The ability to efficiently simulate random quantum circuits using a classical computer is increasingly important for developing Noisy Intermediate-Scale Quantum devices. Here we present a tensor network states based algorithm specifically designed to compute amplitudes for random quantum circuits with arbitrary geometry. Singular value decomposition based compression together with a two-sided circuit evolution algorithm are used to further compress the resulting tensor network. To further accelerate the simulation, we also propose a heuristic algorithm to compute the optimal tensor contraction path. We demonstrate that our algorithm is up to $2$ orders of magnitudes faster than the Sch$\ddot{\text{o}}$dinger-Feynman algorithm for verifying random quantum circuits on the $53$-qubit Sycamore processor, with circuit depths below $12$. We also simulate larger random quantum circuits up to $104$ qubits, showing that this algorithm is an ideal tool to verify relatively shallow quantum circuits on near-term quantum computers.

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Chu Guo, Youwei Zhao, He-Liang Huang. 2020-11-05. Verifying Random Quantum Circuits with Arbitrary Geometry Using Tensor Network States Algorithm. https://doi.org/10.1103/physrevlett.126.070502

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