发表机构
Independent Researcher, Macau 999078, China
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
提出非绝热Floquet协议，在单腔BEC中动态合成TAT相互作用，快速产生海森堡极限自旋压缩，绕过绝热瓶颈，实现微秒级计量。
AI 中文摘要
产生宏观量子纠缠是量子计量的核心。虽然穿越量子临界点能够获得海森堡极限精度，但绝热方案受限于缓慢的动力学和退相干。在此，我们提出一种在单腔玻色-爱因斯坦凝聚体中的非绝热Floquet协议，以规避这些限制。通过施加快速旋转和相位跳变，我们从本征纵向耦合动态合成有效的双轴扭转（TAT）相互作用。为了在平均场极限之外评估该方案，我们开发了一种精确的有限状态自动机矩阵乘积算符（MPO）编码，该编码严格限制虚拟维度为$\mathcal{O}(1)$，从而能够对大系统进行精确的DMRG和TDVP模拟。跟踪非平衡Floquet TAT动力学和环境退相干，对于$N=10^3$系综，我们证明该淬火快速产生海森堡极限的自旋压缩（$\xi_R^2 \sim 1/N$）。该协议的微秒时间尺度将产生过程与典型的毫秒退相干解耦，唯象模型显示最佳提取时间接近$t \approx 3.26~\mu s$。这项工作为在当前腔QED平台中实现海森堡极限计量建立了一条可行路径。
英文摘要
Generating macroscopic quantum entanglement is central to quantum metrology. While traversing a quantum critical point yields Heisenberg-limited precision, adiabatic schemes are restricted by slow dynamics and decoherence. Here, we propose a non-adiabatic Floquet protocol in a single-cavity Bose-Einstein condensate to circumvent these limitations. By applying rapid rotations and phase jumps, we dynamically synthesize effective Two-Axis Twisting (TAT) interactions from native longitudinal couplings. To evaluate this beyond mean-field limits, we develop an exact finite-state automaton Matrix Product Operator (MPO) encoding that strictly bounds the virtual dimension to $\mathcal{O}(1)$, enabling exact DMRG and TDVP simulations for large systems. Tracking non-equilibrium Floquet TAT dynamics and environmental decoherence for $N=10^3$ ensembles, we demonstrate that the quench rapidly generates Heisenberg-limited spin squeezing ($ξ_R^2 \sim 1/N$). The microsecond timescale of this protocol decouples the generation process from typical millisecond decoherence, with phenomenological models revealing an optimal extraction time near $t \approx 3.26~μs$. This work establishes a feasible route for realizing Heisenberg-limited metrology in current cavity-QED platforms.
