Avoiding entanglement sudden-death via measurement feedback control in a quantum network
arXiv:0806.4754 · doi:10.1103/PhysRevA.78.042339
Abstract
In this paper, we consider a linear quantum network composed of two distantly separated cavities that are connected via a one-way optical field. When one of the cavity is damped and the other is undamped, the overall cavity state obtains a large amount of entanglement in its quadratures. This entanglement however immediately decays and vanishes in a finite time. That is, entanglement sudden-death occurs. We show that the direct measurement feedback method proposed by Wiseman can avoid this entanglement sudden-death, and further, enhance the entanglement. It is also shown that the entangled state under feedback control is robust against signal loss in a realistic detector, indicating the reliability of the proposed direct feedback method in practical situations.
11 pages
References in corpus (6)
- Finite-Time Disentanglement via Spontaneous Emission
- Delayed (sudden) birth of entanglement
- Purity of Gaussian states: measurement schemes and time-evolution in noisy channels
- Stabilising entanglement by quantum jump-based feedback
- Optimal control of entanglement via quantum feedback
- Singular perturbation of quantum stochastic differential equations with coupling through an oscillator mode