The Hong–Ou–Mandel effect—in which two indistinguishable photons that enter a 50:50 beam-splitter are found only as a pair at one of the two outputs, leading to a dip in the coincidence rate of the detectors—is now realized with 4He atoms instead of photons; this opens the way to performing basic quantum-physics experiments with mechanical observables of massive particles.
- R. Lopes
- A. Imanaliev
- C. I. Westbrook