近日，辽宁大学的Yusuf Turek与新疆师范大学的Ahmad Abliz合作并取得一项新进展。经过不懈努力，他们成功利用后选择冯·诺依曼测量增强双模压缩真空态的非经典性质。相关研究成果已于2024年11月19日在国际知名学术期刊《物理评论A》上发表。

该研究团队研究了弱值放大对双模压缩真空态非经典特性的影响。通过计算正交压缩度和二阶交叉相关函数，研究人员展示了后选择弱测量（WM）的优势。研究人员还通过评估包括柯西-施瓦茨不等式、Hillery-Zubairy关联和爱因斯坦-波多尔斯基-罗森关联在内的各种纠缠判据，来检验两个模式之间的纠缠情况。

这项研究结果表明，后选择的冯·诺依曼测量显著优化了双模压缩真空态。值得注意的是，弱值的放大效应在此过程中起到了关键作用。研究人员证明，在弱测量条件下，随着弱值的增加，双模压缩真空态的非经典特性，如纠缠和两个模式之间的相关性，与原始状态相比变得更加显著。

研究人员还提出了使用离子阱系统和光学平台来实现该研究方法的可能途径。这种增强的双模压缩真空态可能在量子信息处理领域具有潜在应用，如单光子产生、高级成像技术、量子计算和远距离量子通信。

附：英文原文

Title: Enhancement of nonclassical properties of the two-mode squeezed vacuum state with a postselected von Neumann measurement

Author: Janarbek Yuanbek, Yi-Fang Ren, Ahmad Abliz, Yusuf Turek

Issue&Volume: 2024/11/19

Abstract: We investigate the effects of weak value amplification on the nonclassical properties of the two-mode squeezed vacuum state. We calculate the quadrature squeezing and second-order cross-correlation functions to demonstrate the advantages of postselective weak measurement (WM). We also examine the entanglement between the two modes by evaluating various entanglement criteria, including the Cauchy-Schwartz inequality, Hillery-Zubairy correlation, and Einstein-Podolsky-Rosen correlations. Our results show that postselected von Neumann measurements significantly optimize the two-mode squeezed vacuum state. Notably, the amplification effect of weak values plays a critical role in this process. We demonstrated that in the WM regime, as the weak values increase, the nonclassical properties of the two-mode squeezed vacuum state such as entanglement and correlations between the two modes become more pronounced compared to the original state. We also propose possible implementation methods for our approach using trapped ion systems and optical platforms. Our enhanced two-mode squeezed vacuum state may have potential applications in quantum information processing scenarios, such as single-photon generation, advanced imaging techniques, quantum computation, and long-distance quantum communication.

DOI: 10.1103/PhysRevA.110.052611

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.052611