Persistent fermionic entanglement under decoherence

TL;DR

This paper investigates how entanglement in a two-fermion system persists under decoherence from a bosonic bath, revealing conditions for long-lived entanglement despite environmental noise.

Contribution

It introduces a measure of fermionic entanglement and identifies state families that maintain entanglement despite decoherence, regardless of temperature.

Findings

Certain fermionic states retain entanglement throughout decoherence

Entanglement persistence is independent of bath temperature

Provides insights into long-lived entanglement in open fermionic systems

Abstract

We consider a system of two indistinguishable fermions (with four accessible states each) that suffers decoherence without dissipation due to its coupling with a global bosonic bath at a fixed temperature. Using an appropriate measure of fermionic entanglement, we identify families of two-fermion states whose entanglement persists throughout the evolution, either fully or partially, despite the noisy effects of the interaction with the bath, and independently of its temperature. The identified resilience to decoherence provides valuable insights into the entanglement dynamics of open systems of indistinguishable fermions, and into the conditions under which long-lived entanglement emerges under more general decoherence channels.