Abstract
Einstein-Podolsky-Rosen (EPR) steering is a form of quantum correlation that exhibits a fundamental asymmetry in the properties of quantum systems. Given two observers, Alice and Bob, it is known to exist bipartite entangled states which are one-way steerable in the sense that Alice can steer Bob's state, but Bob cannot steer Alice's state. Here we generalize this phenomenon to three parties and find a cyclic property of tripartite EPR steering. In particular, we identify a three-qubit state whose reduced bipartite states are one-way steerable for arbitrary projective measurements. Moreover, the three-qubit state has a cyclic steering property in the sense, that by arranging the system in a triangular configuration the neighboring parties can steer each others' states only in the same (e.g. clockwise) direction. That is, Alice can steer Bob's state, Bob can steer Charlie's state, and Charlie can steer Alice's state, but not the other way around.
Highlights
Quantum entanglement is a remarkable phenomenon without counterpart in classical physics [1,2]
We show that if we do not restrict the local dimension to a qubit, we can strengthen our findings by generalizing cyclic EPR steering from projective measurements to general positive-operator-valued measure (POVM)
We have shown the existence of three-party states arranged in a triangular configuration, where each two-party reduced state is steerable in one direction, but unsteerable in the other direction
Summary
Quantum entanglement is a remarkable phenomenon without counterpart in classical physics [1,2]. EPR steering can be seen as a form of quantum correlation that is intermediate between entanglement and Bell nonlocality [12,13] To illustrate these properties, let us consider the two-qubit singlet state (1). In the steering problem, Bob’s task is to determine whether the states ρa|x in the assemblage (5) admit a decomposition of the form (7) If this is the case, Bob will not be convinced that entanglement is present. [12], is whether there exists a bipartite entangled state ρAB such that Alice can steer Bob’s state, but Bob cannot steer Alice’s state This phenomenon, which has been called one-way steering, was first investigated theoretically in continuous variable systems for a restricted class of measurements [37,38]. Been studied in the context of steering for three-qubit systems [47]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
