Entanglement in Weisskopf-Wigner theory of atomic decay in free space

TL;DR

This paper explores how atomic decay in free space generates entanglement in the radiation field using Weisskopf-Wigner theory, revealing its role in atomic decay dynamics and mode partitioning.

Contribution

It applies Weisskopf-Wigner theory to analyze entanglement in free-space radiation, highlighting the impact of partition size and detuning on bipartite entanglement.

Findings

Entanglement is shared among different radiation mode partitions.

Partition size and detuning influence the amount of entanglement.

Entanglement dynamics relate to atomic decay time.

Abstract

In this paper, we use the Weisskopf-Wigner theory to study the entanglement in the state of the free-space radiation field produced from vacuum due to atomic decay. We show how bipartite entanglement is shared between different partitions of the radiation modes. We investigate the role played by the size of the partitions and their detuning with the decaying atom. The dynamics of the atom-field entanglement during the atomic decay is also briefly discussed. From this dynamics, we assert that such entanglement is the physical quantity that fix the statistical atomic decay time.