发表机构
School of Physics and Electronic Engineering, Shanxi Normal University（山西师范大学物理与电子工程学院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出利用频率乘积态和后选择频率反相关结果，证明多模HOM计量优势源于频谱反相关而非纠缠或玻色子对称性，无需强泵浦激光，便于实际应用。
AI 中文摘要
多模频域中的Hong-Ou-Mandel（HOM）干涉已广泛用于精密计量，得益于其对色散和相位噪声的鲁棒性，以及大动态范围和与脆弱样品的兼容性。传统多模HOM计量利用频率纠缠态，这些态在任意中心对称联合频谱分布下自然满足玻色子交换对称性，从而提供上述优势。然而，这些纠缠态通常通过自发参量下转换（SPDC）产生，需要强泵浦激光器，阻碍了实际应用。在本文中，我们采用频率乘积态（不具有纠缠或路径模式交换对称性）作为探针态，并后选择表现出频率反相关的测量结果。我们的结果表明，这些计量优势既不源于纠缠，也不源于玻色子交换对称性，而是源于频谱反相关。
英文摘要
The Hong-Ou-Mandel (HOM) interference in the multimode frequency domain has been explored for precision metrology, with several experimental demonstrations exploiting its robustness against dispersion and phase noise, as well as its large dynamic range and compatibility with fragile samples. Conventional multimode HOM metrology exploits frequency-entangled states, which naturally satisfy bosonic exchange symmetry under any centered symmetric joint spectral distribution, to provide these advantages. However, these entangled states are typically generated via spontaneous parametric down-conversion (SPDC), requiring strong pump lasers that hinder practical implementation. In this paper, we employ frequency product states, which do not possess entanglement or path-mode exchange symmetry, as the probe state and post-select measurement outcomes exhibiting frequency anti-correlation. Our results demonstrate that these advantages,peak narrowing, dispersion cancellation, phase-noise immunity, a large dynamic range, and compatibility with fragile samples, arise neither from entanglement nor from bosonic exchange symmetry, but rather from spectral anti-correlation. We further show that entanglement is not the source of the measurement precision: the entanglement-free approach attains the same quantum Fisher information as the entangled-state scheme, indicating that the fundamental precision limit does not originate from entanglement.
Comments17 pages, 4 figures
