发表机构
Shangrao Normal University; Hangzhou Normal University（上饶师范学院; 杭州师范大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究将协变量子费舍尔信息扩展至多模非厄米SSH晶格，借助非布洛赫皮肤效应实现拓扑增强，可显著提升量子计量精度，且具有实验可行性。
AI 中文摘要
协变量子费舍尔信息（CQFI）近期被确立为伪厄米传感器的终极精度基准[Phys. Rev. Lett. 136, 080802 (2026)]，但现有分析仅局限于单模系统。本文将CQFI形式主义扩展至多模非厄米Su-Schrieffer-Heeger（SSH）晶格，揭示了由非厄米皮肤效应（NHSE）实现的可调拓扑增强。在开放边界条件下，NHSE将常规布里渊区变形为半径r = exp(κ)的广义布里渊区，其中κ为非布洛赫衰减率。总CQFI随系统尺寸N线性缩放，其 prefactor 高度依赖κ，产生增强因子E(N) = F_OBC / F_PBC，当N≈30时该因子超过30，显著优于周期边界传感器。该增强对中等局域噪声具有鲁棒性，且支持多参数估计，联合克拉美罗界可降低多达15个数量级。这些发现为量子计量学建立了一种空间域机制，可补充时域策略，且利用现有技术（拓扑电路、光子晶格、超导电路）可实现实验验证。
英文摘要
The covariant quantum Fisher information (CQFI) has recently been established as the ultimate precision benchmark for pseudo-Hermitian sensors [Phys. Rev. Lett. 136, 080802 (2026)], yet existing analyses are limited to single-mode systems. Here we extend the CQFI formalism to multi-mode non-Hermitian Su-Schrieffer-Heeger lattices and reveal tunable topological enhancement enabled by the non-Hermitian skin effect (NHSE). Under open boundary conditions, the NHSE deforms the conventional Brillouin zone into a generalized Brillouin zone of radius r = exp(\k{appa}), where \k{appa} denotes the non-Bloch decay rate. While the total CQFI scales linearly with system size N, its prefactor depends critically on \k{appa}, yielding an enhancement factor E(N) = F_OBC / F_PBC that exceeds 30 for N ~ 30, substantially outperforming periodic-boundary sensors. The enhancement is robust against moderate local disorder and supports multi-parameter estimation, with the joint Cramér-Rao bound reduced by up to 15 orders of magnitude. These findings establish a spatial-domain mechanism for quantum metrology that complements time-domain strategies and is experimentally accessible using topoelectrical circuits, photonic lattices, and superconducting circuits with current technology.
Comments10 pages, 4 figures
