Macroscopic position-position entanglement by photon recoil in Rydberg atoms

Entanglement between two spatially separate matter particles can be generated via many means and often resides in the internal states of particles.

Here, via Rydberg blockade in two spatially separate neutral atoms, we find that the photon recoil in Rydberg excitation can push one atom microns away provided the other atom exerts a state-dependent Rydberg-mediated blockade.

When the atoms are recaptured by optical traps, a position-position entangled state between two spatially separate atoms can emerge.

This realizes a Bell state of two atoms, where the entanglement exists in the position of each atom and the distance between the two possible locations of each atom can be in the hundred-micron regime.