Efficient synchronization of single photons that are compatible with narrow band atomic transitions is an outstanding challenge, which could prove essential for photonic quantum information processing. Here we report on the synchronization of independently generated single photons using a room-temperature atomic quantum memory. The photon source and the memory are interconnected by fibers and employ the same ladder-level atomic scheme. We store and retrieve the heralded single photons with end-to-end efficiency of ${\eta }_{\mathrm{e}2\mathrm{e}}=25\%$ and final antibunching of $g_h^{(2)}=0.023$. Our synchronization process results in an over tenfold increase in the photon-pair coincidence rate, reaching a rate of more than 1000 detected synchronized photon pairs per second. The indistinguishability of the synchronized photons is verified by a Hong-Ou-Mandel interference measurement.

Close

PrevNext

View figure in article

• Quantum optics
• Quantum states of light
• Atomic ensemble
• Four-wave mixing
• Photon counting