arXiv:1011.5348 · Physical Review A
Evolution equation for entanglement of multiqubit systems
Michael Siomau, S. Fritzsche
Abstract
We discuss entanglement evolution of a multiqubit system in which one of its qubits is subjected to a general noisy channel. For such a system, an evolution equation of entanglement for a lower bound for multiqubit concurrence is derived. Using this evolution equation, the entanglement dynamics of an initially mixed three-qubit state composed of a Greenberger-Horne-Zeilinger (GHZ) and a $W$ state is analyzed if one of the qubits is affected by a phase, an amplitude, or a generalized amplitude damping channel.