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arXiv · 2106.01445

Cracking the Quantum Advantage threshold for Gaussian Boson Sampling

A. S. Popova·A. N. Rubtsov
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Abstract

Scientists in quantum technology aspire to quantum advantage: a computational result unattainable with classical computers. Gaussian boson sampling experiment has been already claimed to achieve this goal. In this setup squeezed light states interfere in a mid-sized linear optical network, where multi-photon collisions take place. The exact simulation of the counting statistics of $n$ threshold detectors is far beyond the possibilities of modern supercomputers once $n$ exceeds $100$. Here we challenge quantum advantage for a mid-sized Gaussian boson sampling setup and propose the approximate algorithm to obtain the probability of any specific measurement outcome. For an 70-mode device on a laptop, our approximation achieves accuracy competitive with the experimental one.

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A. S. Popova, A. N. Rubtsov. 2021-06-02. Cracking the Quantum Advantage threshold for Gaussian Boson Sampling. https://arxiv.org/abs/2106.01445

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