Transferring entanglement to the steady-state of flying qubits

TL;DR

This paper explores a method for transferring entanglement from cavity-driven optical fields to flying qubits, enabling remote quantum entanglement without the need for simultaneous atom trapping.

Contribution

It introduces a novel scheme for entanglement transfer from driven cavities to flying qubits, addressing practical challenges in atom trapping and synchronization.

Findings

Entanglement transfer is effective with long cavity coherence times.

Unitary dynamics enable strong entanglement transfer.

Dissipation-dominated regimes result in weak quantum correlations.

Abstract

The transfer of entanglement from optical fields to qubits provides a viable approach to entangling remote qubits in a quantum network. In cavity quantum electrodynamics, the scheme relies on the interaction between a photonic resource and two stationary intracavity atomic qubits. However, it might be hard in practice to trap two atoms simultaneously and synchronize their coupling to the cavities. To address this point, we propose and study entanglement transfer from cavities driven by an entangled external field to controlled flying qubits. We consider two exemplary non-Gaussian driving fields: NOON and entangled coherent states. We show that in the limit of long coherence time of the cavity fields, when the dynamics is approximately unitary, entanglement is transferred from the driving field to two atomic qubits that cross the cavities. On the other hand, a dissipation-dominated dynamics leads to very weakly quantum-correlated atomic systems, as witnessed by vanishing quantum discord.