Exact gate decompositions for photonic quantum computing

@article{Kalajdzievski2019ExactGD,
  title={Exact gate decompositions for photonic quantum computing},
  author={Timjan Kalajdzievski and Juan Miguel Arrazola},
  journal={Physical Review A},
  year={2019}
}
We propose a method for decomposing continuous-variable operations into a universal gate set, without the use of any approximations. We fully characterize a set of transformations admitting exact decompositions and describe a process for obtaining them systematically. Gates admitting these decompositions can be synthesized exactly, using circuits that are several orders of magnitude smaller than those achievable with previous methods. Our method relies on strategically using unitary conjugation… 

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