Direct characterization of linear-optical networks.

  title={Direct characterization of linear-optical networks.},
  author={Saleh Rahimi-Keshari and Matthew A. Broome and Robert Fickler and Alessandro Fedrizzi and Timothy C. Ralph and Andrew G. White},
  journal={Optics express},
  volume={21 11},
We introduce an efficient method for fully characterizing multimode linear-optical networks. Our approach requires only a standard laser source and intensity measurements to directly and uniquely determine all moduli and non-trivial phases of the matrix describing a network. We experimentally demonstrate the characterization of a 6×6 fiber-optic network and independently verify the results via nonclassical two-photon interference. 

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