A fully guided-wave squeezing experiment for fiber quantum networks

Squeezed light is a fundamental resource for quantum communication. In view of its real-world applications, the realization of easy-to-operate experimental systems compatible with existing fiber networks is a crucial step. To comply with these requirements, we demonstrate the feasibility of a squeezing experiment at a telecom wavelength realized, for the first time, in an entirely guided-wave fashion. In our work, the state generation relies on waveguide nonlinear optics technology while squeezing collection and transmission are implemented by using only telecom fiber components. By doing so, we observe up to -1.83 +/- 0.05 dB of squeezing emitted at 1542 nm in the CW pumping regime. The compactness and stability of the experiment, compared to free-space configurations, represent a significant advance towards achieving out-of-the-lab continuous variable quantum communications that are fully compatible with long-distance operations in telecom fibers. We believe that this work stands as a promising approach for real applications as well as for "do-it-yourself" experiments. (C) 2016 Optical Society of America