Engineering integrated photonics for heralded quantum gates

  title={Engineering integrated photonics for heralded quantum gates},
  author={Thomas Meany and Devon N. Biggerstaff and Matthew A. Broome and Alessandro Fedrizzi and Michael Delanty and Michael J. Steel and Alexei Gilchrist and Graham D. Marshall and Andrew G. White and Michael J. Withford},
  journal={Scientific Reports},
Scaling up linear-optics quantum computing will require multi-photon gates which are compact, phase-stable, exhibit excellent quantum interference, and have success heralded by the detection of ancillary photons. We investigate the design, fabrication and characterisation of the optimal known gate scheme which meets these requirements: the Knill controlled-Z gate, implemented in integrated laser-written waveguide arrays. We show device performance to be less sensitive to phase variations in the… 

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