# Single-Photon Pulse Induced Transient Entanglement Force

## TL;DR

This paper demonstrates that a single-photon pulse can induce a transient entanglement force between two atoms, which can be tuned and enhanced, offering new ways to manipulate and observe atom-atom entanglement.

## Contribution

It reveals that shaped single-photon pulses induce a tunable, transient entanglement force between atoms, with potential enhancement via graphene plasmons.

## Key findings

- SPP induces a transient entanglement force between atoms.
- The force can be tuned from repulsive to attractive by polarization.
- Graphene plasmons can enhance the entanglement force by over three orders of magnitude.

## Abstract

We show that a single photon pulse (SPP) incident on two interacting two-level atoms induces a transient entanglement force between them. After absorption of a multi-mode Fock state pulse, the time-dependent atomic interaction mediated by the vacuum fluctuations changes from the van der Waals interaction to the resonant dipole-dipole interaction (RDDI). We explicitly show that the RDDI force induced by the SPP fundamentally arises from the two-body transient entanglement between the atoms. This SPP induced entanglement force can be continuously tuned from being repulsive to attractive by varying the polarization of the pulse. We further demonstrate that the entanglement force can be enhanced by more than three orders of magnitude if the atomic interactions are mediated by graphene plasmons. These results demonstrate the potential of shaped SPPs as a powerful tool to manipulate this entanglement force and also provides a new approach to witness transient atom-atom entanglement.