Hastening, delaying, or averting sudden death of quantum entanglement

The finite time end of entanglement between two decohering qubits can be modified by local, unitary actions performed during the decoherence process. Depending on the time when such action is taken, the end can be speeded up or slowed down, or even averted all together. This phenomenon offers practical applications for the stabilization of entangled quantum states. Details concerning hastening or delaying the finite-time end of entanglement are presented for two qubits which decay spontaneously into statistically independent reservoirs.