摘要
The long-range interaction between Rydberg-excited atoms endows a medium with large optical nonlinearity.Here,we demonstrate an optical switch to operate on a single photon from an entangled photon pair under a Rydberg electromagnetically induced transparency configuration.With the presence of the Rydberg blockade effect,we switch on a gate field to make the atomic medium nontransparent thereby absorbing the single photon emitted from another atomic ensemble via the spontaneous fourwave mixing process.In contrast to the case without a gate field,more than 50%of the photons sent to the switch are blocked,and finally achieve an effective single-photon switch.There are on average 1-2 gate photons per effective blockade sphere in one gate pulse.This switching effect on a single entangled photon depends on the principal quantum number and the photon number of the gate field.Our experimental progress is significant in the quantum information process especially in controlling the interaction between Rydberg atoms and entangled photon pairs.
基金
supported by the National Key Research and Development Program of China(Grant No.2017YFA0304800)
the National Natural Science Foundation of China(Grant Nos.61525504,61722510,61435011,11174271,61275115,and 11604322)
the Anhui Initiative in Quantum Information Technologies(Grant No.AHY020200)
the Youth Innovation Pro motion Association of Chinese Academy of Sciences(Grant No.2018490)。
