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.
@article{arxiv.1906.08709,
title = {Deterministic generation of a two-dimensional cluster state},
author = {Mikkel V. Larsen and Xueshi Guo and Casper R. Breum and Jonas S. Neergaard-Nielsen and Ulrik L. Andersen},
journal= {arXiv preprint arXiv:1906.08709},
year = {2019}
}