Entanglement dynamics in open two-qubit systems via diffusive quantum trajectories

TL;DR

This paper demonstrates how continuous monitoring of open two-qubit systems via diffusive quantum trajectories can fully characterize entanglement dynamics, providing analytical tools and experimental proposals for real-time entanglement monitoring.

Contribution

It introduces an optimal unraveling for entanglement evolution and derives a deterministic equation for concurrence, advancing understanding of open quantum system dynamics.

Findings

Analytical determination of optimal unraveling

Derivation of a deterministic concurrence evolution equation

Proposal for experimental entanglement monitoring

Abstract

We use quantum diffusive trajectories to prove that the time evolution of two-qubit entanglement under spontaneous emission can be fully characterized by optimal continuous monitoring. We analytically determine this optimal unraveling and derive a deterministic evolution equation for the system's concurrence. Furthermore, we propose an experiment to monitor the entanglement dynamics in bipartite two-level systems and to determine the disentanglement time from a single trajectory.