Mechanical rotation modifies the manifestation of photon entanglement

Mechanical rotation plays a central role in fundamental physics theories and has profound connections with the theory of general relativity. However, very few experiments have so far aimed to explore the interplay of mechanical rotation with entangled photon states. By adding Sagnac interferometers into the arms of a Hong-Ou-Mandel (HOM) interferometer that is placed on a mechanically rotating platform, we experimentally observe the modification of the symmetry of an entangled biphoton state due to noninertial motion. As the platform rotation speed is increased, we observe that HOM interference dips transform into HOM interference peaks. This indicates that the photons pass from perfectly indistinguishable (bosonic behavior), to perfectly distinguishable (fermionic behavior). This demonstration is of relevance to global satellite quantum communications and paves the way for further fundamental research that can test the influence of curved space on quantum entanglement.