Quantification of Short Coherence Time Photon Pair Indistinguishability Using Hong-Ou-Mandel Interferometry

We conducted interference characterization on near-infrared photons generated from a beta barium borate non-linear crystal excited by a pulsed laser. The observed photons demonstrated a coherence time of 86.52 fs, with interference visibility reaching up to 89.5%. This proof-of-concept experiment underscores the remarkable indistinguishability of beta barium borate photons, highlighting their promise for future applications, particularly in Quantum Optical Coherence Tomography (QOCT) research.