近日，南方科技大学的俞大鹏及其研究小组与中国科学技术大学的邹长铃等人合作并取得一项新进展。经过不懈努力，他们揭示具有大福克态的量子增强计量学。相关研究成果已于2024年8月20日在国际知名学术期刊《自然—物理学》上发表。

本文提出了一种高效的方法，通过开发可编程光子数滤波器，在超导微波腔内生成接近100个光子的大福克态。研究人员将这些态应用于位移和相位测量，展示了量子增强计量学接近40光子福克态的海森堡缩放，并实现了最大计量增益高达14.8dB，凸显了大福克态的计量优势。这项研究可以很容易地扩展到机械和光学系统，有望在微弱力检测和暗物质搜索等领域得到应用。

据悉，量子计量学利用非经典态，如具有特定光子数的福克态，以获得相对于经典传感方法的优势。通常，可以通过增加所涉及的激发数来增强量子计量性能，例如，通过使用大光子数福克态。然而，在实验上操控这些态并证明量子计量的优势是具有挑战性的。

附：英文原文

Title: Quantum-enhanced metrology with large Fock states

Author: Deng, Xiaowei, Li, Sai, Chen, Zi-Jie, Ni, Zhongchu, Cai, Yanyan, Mai, Jiasheng, Zhang, Libo, Zheng, Pan, Yu, Haifeng, Zou, Chang-Ling, Liu, Song, Yan, Fei, Xu, Yuan, Yu, Dapeng

Issue&Volume: 2024-08-20

Abstract: Quantum metrology uses non-classical states, such as Fock states with a specific number of photons, to achieve an advantage over classical sensing methods. Typically, quantum metrological performance can be enhanced by increasing the involved excitation numbers, for example, by using large-photon-number Fock states. However, manipulating these states and demonstrating a quantum metrological advantage is experimentally challenging. Here we present an efficient method for generating large Fock states approaching 100 photons within a superconducting microwave cavity through the development of a programmable photon number filter. Using these states in displacement and phase measurements, we demonstrate quantum-enhanced metrology approaching the Heisenberg scaling for 40-photon Fock states and achieve a maximum metrological gain of up to 14.8dB, highlighting the metrological advantages of large Fock states. Our study could be readily extended to mechanical and optical systems, promising potential applications in weak force detection and dark matter searches.

DOI: 10.1038/s41567-024-02619-5

Source: https://www.nature.com/articles/s41567-024-02619-5