# Critical slowing down and entanglement protection

## TL;DR

This paper investigates how critical slowing down near a quantum phase transition can be exploited to protect entanglement in a quantum device by controlling its environment, using the Kibble-Zurek mechanism and magnetic domain formation.

## Contribution

It introduces a novel strategy to preserve entanglement in quantum devices by leveraging environment dynamics at criticality, specifically through magnetic domain control.

## Key findings

- Environment can be frozen in a beneficial configuration near criticality.
- Entanglement protection is achievable via environment manipulation.
- Critical slowing down reduces environmental impact on quantum coherence.

## Abstract

We consider a quantum device $D$ interacting with a quantum many-body environment $R$ which features a second-order phase transition at $T=0$. Exploiting the description of the critical slowing down undergone by $R$ according to the Kibble-Zurek mechanism, we explore the possibility to freeze the environment in a configuration such that its impact on the device is significantly reduced. Within this framework, we focus upon the magnetic-domain formation typical of the critical behaviour in spin models, and propose a strategy that allows one to protect the entanglement between different components of $D$ from the detrimental effects of the environment.