Entanglement of Two Individual Neutral Atoms Using Rydberg Blockade

TLDR

The study aims to generate entanglement between two individual 87Rb atoms in hyperfine ground states |F=1,M=1> and |F=2,M=2> confined in optical tweezers 4 µm apart. Entanglement is produced in ~200 ns by pulsed two‑photon excitation exploiting the Rydberg blockade, and its fidelity is assessed with global Raman rotations. The protocol retains 61 % of atom pairs and achieves an entangled‑state fidelity of 0.75.

Abstract

We report the generation of entanglement between two individual 87Rb atoms in hyperfine ground states |F=1,M=1> and |F=2,M=2> which are held in two optical tweezers separated by 4 microm. Our scheme relies on the Rydberg blockade effect which prevents the simultaneous excitation of the two atoms to a Rydberg state. The entangled state is generated in about 200 ns using pulsed two-photon excitation. We quantify the entanglement by applying global Raman rotations on both atoms. We measure that 61% of the initial pairs of atoms are still present at the end of the entangling sequence. These pairs are in the target entangled state with a fidelity of 0.75.