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arXiv · 1906.08709

Deterministic generation of a two-dimensional cluster state

Mikkel V. Larsen·Xueshi Guo·Casper R. Breum·Jonas S. Neergaard-Nielsen·Ulrik L. Andersen
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Abstract

Measurement-based quantum computation offers exponential computational speed-up via simple measurements on a large entangled cluster state. We propose and demonstrate a scalable scheme for the generation of photonic cluster states suitable for universal measurement-based quantum computation. We exploit temporal multiplexing of squeezed light modes, delay loops, and beam-splitter transformations to deterministically generate a cylindrical cluster state with a two-dimensional (2D) topological structure as required for universal quantum information processing. The generated state consists of more than 30000 entangled modes arranged in a cylindrical lattice with 24 modes on the circumference, defining the input register, and a length of 1250 modes, defining the computation depth. Our demonstrated source of 2D cluster states can be combined with quantum error correction to enable fault-tolerant quantum computation.

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Mikkel V. Larsen, Xueshi Guo, Casper R. Breum, Jonas S. Neergaard-Nielsen, Ulrik L. Andersen. 2019-06-20. Deterministic generation of a two-dimensional cluster state. https://doi.org/10.1126/science.aay4354

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