近日，中国人民大学的张威及其研究小组与北京量子信息科学研究院的Zhiyue Zheng等人合作并取得一项新进展。经过不懈努力，他们基于设备无关局部性实验排除联合现实。相关研究成果已于2024年1月19日在国际知名学术期刊《中国物理快报》上发表。

该研究团队在一个双量子比特超导系统上实施了一项与设备无关的实验，旨在证明在单个时空区域（或单个量子比特）中观测到的现实较弱的前提下，两个观测结果之间的联合现实与局部性是不相容的。实验结果明确地揭示了某些由线性和非线性准则推导出的不等式被违反。此外，研究团队还深入探讨了线性和非线性准则对于系统退相干影响的稳健性。这一演示为利用更简单的非平凡量子系统来描绘经典与非经典之间的界限提供了新的可能性。

据悉，作为理解世界的基本概念之一，可观测物的真实值（或物理现实）是否适用于超越经典的物理系统一直是几十年来争论的焦点。尽管基于贝尔不等式的标准未通过结果已经排除了不相容量子可观测物的联合现实，但近期在所有物理系统（包括非量子系统）中，使用较弱的假设和较少的可观测物，人们探索并提出了简单而有力的论据来排除联合现实的可能性。

附：英文原文

Title: Experimentally Ruling Out Joint Reality Based on Locality with Device-Independent Steering

Author:Shuaining Zhang, Xiang Zhang, Zhiyue Zheng, and Wei Zhang

Issue&Volume: 2024-01-19

Abstract: As an essential concept to understand the world, whether the real values (or physical realities) of observables are suitable to physical systems beyond the classic has been debated for many decades. Although standard no-go results based on Bell inequalities have ruled out the joint reality of incompatible quantum observables, the possibility of giving simple yet strong arguments to rule out joint reality in any physical system (not necessarily quantum) with weaker assumptions and less observables has been explored and proposed recently. Here, we perform a device-independent experiment on a two-qubit superconducting system to show that the joint reality of two observables is incompatible with locality under the weaker assumption of the reality of observables in a single space-time region (or single qubit). Our results clearly show the violation of certain inequalities derived from both linear and nonlinear criteria. In addition, we study the robustness of the linear and nonlinear criterion against the effect of systematic decoherence. Our demonstration opens up the possibility of delineating classical and non-classical boundaries with simpler nontrivial quantum system.

DOI: 10.1088/0256-307X/41/1/010301

Source: https://cpl.iphy.ac.cn/10.1088/0256-307X/41/1/010301