  We present a Heralded Photon Source based only on linear optics and weak
coherent states. By time-tuning a Hong-Ou-Mandel interferometer fed with
frequency-displaced coherent states, the output photons can be synchronously
heralded following sub-Poisson statistics, which is indicated by the
second-order correlation function ($g^2\left(0\right)=0.556$). The absence of
phase-matching restrictions makes the source widely tunable, with 100-nm
spectral tunability on the telecom bands. The technique presents yield
comparable to state-of-the-art spontaneous parametric down-conversion-based
sources, with high coherence and fiber-optic quantum communication
compatibility.
