The robust operation of quantum entanglement states is crucial for applications in quantum information,computing,and communications^(1–3).However,it has always been a great challenge to complete such a task because o...The robust operation of quantum entanglement states is crucial for applications in quantum information,computing,and communications^(1–3).However,it has always been a great challenge to complete such a task because of decoherence and disorder.Here,we propose theoretically and demonstrate experimentally an effective scheme to realize robust operation of quantum entanglement states by designing quadruple degeneracy exceptional points.By encircling the exceptional points on two overlapping Riemann energy surfaces,we have realized a chiral switch for entangled states with high fidelity.Owing to the topological protection conferred by the Riemann surface structure,this switching of chirality exhibits strong robustness against perturbations in the encircling path.Furthermore,we have experimentally validated such a scheme on a quantum walk platform.Our work opens up a new way for the application of non-Hermitian physics in the field of quantum information.展开更多
基金supported by the National key R&D Program of China under Grant No.2022YFA1404904the National Natural Science Foundation of China(12234004 and 12374323).
文摘The robust operation of quantum entanglement states is crucial for applications in quantum information,computing,and communications^(1–3).However,it has always been a great challenge to complete such a task because of decoherence and disorder.Here,we propose theoretically and demonstrate experimentally an effective scheme to realize robust operation of quantum entanglement states by designing quadruple degeneracy exceptional points.By encircling the exceptional points on two overlapping Riemann energy surfaces,we have realized a chiral switch for entangled states with high fidelity.Owing to the topological protection conferred by the Riemann surface structure,this switching of chirality exhibits strong robustness against perturbations in the encircling path.Furthermore,we have experimentally validated such a scheme on a quantum walk platform.Our work opens up a new way for the application of non-Hermitian physics in the field of quantum information.
