Dividing two-qubit Hilbert space via abrupt and asymptotic disentanglement
Peng Li, Qun Zhang, J. Q. You · Physical Review A · 2009
We theoretically show that according to the disentanglement behavior under a composite noise environment, the Hilbert space of a two-qubit system can be divided into two separate parts: a three-dimensional subspace in which all states disentangle asymptotically, and the rest in which all states disentangle abruptly. The violation of additivity for entanglement decay rates under weak noises [Phys. Rev. Lett. 97, 140403 (2006)] can be explained using such Hilbert-space division.