Entanglement witnessing by arbitrarily many pairs of sequential observers
A bilateral sequential entanglement detection problem is examined for 2-qubit entangled states with noise.A class of states that can realize infinite pairs of Alice and Bob sharing entanglement is found based on entanglement witnesses and measurement strategy.Concrete proof is given for the entanglement of states that can be shared by arbitrary Alice-Bob pairs.The 2-qubit maximally entangled state,general entangled pure states,and Werner state,which are special scenarios of such states,are also investigated using specific illustrations.Achieving bilateral entanglement sharing for arbitrary pairs of observers of a bipartite system with noise has important implications in multilateral multiuser scenarios and quantum networks.