# Rydberg atom entanglements in the weak coupling regime

## TL;DR

This paper proposes a novel entanglement scheme for Rydberg atoms utilizing van der Waals interactions, enabling controlled phase operations and complex entanglement states beyond traditional blockade limits, demonstrated experimentally with rubidium atoms.

## Contribution

It introduces a new entanglement method for Rydberg atoms that works beyond the blockade regime, including complex multi-atom entanglement states, with experimental validation.

## Key findings

- Successful generation of two-atom entanglement beyond blockade distance
- Creation of W-states with three partially-blockaded atoms
- Experimental demonstration using rubidium atoms in optical tweezers

## Abstract

We present an entanglement scheme for Rydberg atoms using the van der Waals interaction phase induced by Ramsey-type pulsed interactions. This scheme realizes not only controlled phase operations between atoms at a distance larger than Rydberg blockade distance, but also various counter-intuitive entanglement examples, including two-atom entanglement in the presence of a closer third atom and $W$-state generation for partially-blockaded three atoms. Experimental realization is conducted with single rubidium atoms loaded in an array of optical tweezer dipole traps, to demonstrate the proposed entanglement generations and measurements.