Demonstration of Lossy Linear Transformations and Two-Photon Interference via Singular Value Decomposition

Photon-state transformations are the cornerstone of quantum optics. Recently a universal method to treat non-unitary transformations has been proposed [1] – [3] , based on singular value decomposition. In this work, we show an experimental demonstration of this approach with non-classical light, by studying the dynamics of photon pairs in a system of coupled waveguides.