郑州大学徐鹏团队近日研究了具有SU（1,1）回波的广义非线性干涉仪。这一研究成果发表在2025年5月12日出版的《物理评论A》杂志上。

精确测量在测试理论模型和探索新物理学方面发挥着关键作用。线性拉姆齐干涉仪被广泛用于测量物理量，增强量子计量，甚至接近海森堡极限。然而，线性干涉仪特别容易受到检测噪声的影响，这限制了它们的实际应用。研究组提出了一种扩展的SU（1,1）回波方法来实现对检测噪声有弹性的广义非线性干涉仪。 

通过将其应用于两个不同的模型证明了这种方法的实用性：Lipkin-Meshkov Glick模型和自旋混合动力学。数值模拟证实了该方法的有效性。此外，研究组确定了选择回声条件的权衡，这可以用来进一步提高估计精度。该建议可以很容易地在许多平台上实现，如玻色-爱因斯坦凝聚态、里德伯原子和极性分子，以增强时间和场强的计量。

附：英文原文

Title: Generalized nonlinear interferometer with SU(1,1) echo

Author: Rui Chen, Peng Xu, Shi-Lei Su, Gao-Xiang Li

Issue&Volume: 2025/05/12

Abstract: Precision measurements play a pivotal role in testing theoretical models and exploring new physics. Linear Ramsey interferometer is widely employed for measuring physical quantities, enhancing quantum metrology even approaching the Heisenberg limit. However, the linear interferometer is notably susceptible to detection noise, which limits their practical applications. In this paper, we propose an extended SU(1, 1) echo method to realize a generalized nonlinear interferometer, which is resilient to the detection noise. We demonstrate the utility of this approach by applying it to two distinct models: the Lipkin-Meshkov-Glick model and spin-mixing dynamics. Numerical simulations confirm the effectiveness of our proposed method. Additionally, we identify a trade-off in selecting the echoing conditions, which can be utilized to further enhance estimation precision. Our proposal may be easily implemented in many platforms, such as Bose-Einstein condensate, Rydberg atoms, and polar molecules, to enhance the metrology of time and field strength.

DOI: 10.1103/PhysRevA.111.053709

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.111.053709