含噪声的三体量子非局域共享的持久性

Persistency of tripartite nonlocality sharing with noise

量子非局域共享问题是量子通信中的一类基本问题.目前通过违反Mermin不等式和NS不等式证明了有无限个独立的Charlies可以与一对Alice和Bob共享标准三体量子非局域性和真正无信号非局域性.然而,上述结论是在理想状态下得出的,在实际操作过程中不可避免地会受到各种噪声的影响,这些因素都可能导致量子非局域性的减弱甚至消失.本文主要针对含有噪声的三体量子共享非局域性的持久性问题进行一系列分析.证明了即使在噪声环境下,单个Alice和Bob仍然可以与任意多个Charlies共享标准三体量子非局域性的充分条件.此外还给出了在非理想状态下,任意多个独立的Charlies与一对Alice和Bob共享真正无信号非局域性的充分条件.结果表明,即使在非理想的条件下,只要噪声参数满足相应的条件,标准三体量子非局域性和真正无信号量子非局域性仍然可以在多方之间安全地共享,这可以为实际量子通信过程提供有价值的参考.

Recently,researchers have proven that an infinite number of Charlies and a pair of Alice and Bob can share standard tripartite nonlocality and genuinely nonsignal nonlocality by violating the Mermin and NS inequalities within tripartite systems.This discovery undoubtedly provides new perspectives and potential in quantum information science.However,it should be noted that the above-mentioned conclusion is derived on the highly idealized assumption that the quantum system is perfect and free from external disturbances.In reality,the realization of this ideal state is a challenging proposition.As a fundamental aspect of quantum mechanics,the phenomenon of quantum entanglement is susceptible to the influence of external factors,such as noise,during its practical implementation.Additionally,the process of quantum measurement can introduce potential errors,which may potentially diminish or even negate the observed quantum nonlocality.In light of the above situation,we investigate whether it is possible to share the corresponding quantum nonlocality,despite the inevitable occurrence of noise and error.This paper aims to study and discuss the persistency of nonlocality in noisy three-qubit systems.Firstly,the sufficient conditions are provided for Alice and Bob to share standard tripartite nonlocality with any number of Charlies,even when measurements are noisy and the initial three-qubit system is in a maximally entangled state with noise.This finding indicates that certain standard tripartite nonlocality can persist under non-ideal conditions as long as certain conditions are met.Moreover,this article elucidates the necessary conditions for multiple independent Charlies to share genuinely nonsignal nonlocality with a pair of Alice and Bob in a non-ideal state.This implies that despite the presence of noise and errors,this type of genuinely nonsignal nonlocality can still be securely shared among multiple parties as long as specific conditions are met.This research provides a new theoretical basis for the security and feasibility of quantum communication.The comprehensive analysis presented in this paper offers insights into the behavior of triple quantum nonlocality under noiseless conditions.