Distillation of entanglement between distant systems by repeated measurements on an entanglement mediator

Abstract

A recently proposed purification method, in which Zeno-like measurements of a subsystem can bring about a distillation of another subsystem in interaction with the former, is utilized to yield entangled states between distant systems. It is shown that measurements of a two-level system, locally interacting with two other spatially separated uncoupled subsystems, can distill entangled states from the latter irrespective of the initial states of the two subsystems.