发表机构
Inner Mongolia University; Research Center for Quantum Physics and Technologies, Inner Mongolia University; School of Physical Science and Technology, Inner Mongolia University; Graduate School of China Academy of Engineering Physics（内蒙古大学; 内蒙古大学量子物理与技术研究中心; 内蒙古大学物理科学与技术学院; 中国工程物理研究院研究生院）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究扩展反作用规避策略至Kerr参量振荡器，证明零差监测在耗散临界点实现超越标准量子极限的光子数标度，并引入改进收敛的时间离散方法以高效计算经典Fisher信息。
AI 中文摘要
驱动-耗散Kerr参量振荡器中的耗散相变为实现基于连续测量的临界增强量子传感提供了一条有前景的途径。然而，通过实际测量方案实现这种增强仍然是一个突出的挑战。在此，我们扩展了先前工作中针对高斯线性情形引入的反作用规避策略[arXiv:2511.22248 (2025)]，以分析在耗散临界点处量子与经典Fisher信息如何随Kerr非线性标度。我们的结果表明，反作用规避零差监测实现了超越标准量子极限的增强光子数标度，并显著优于连续光子计数等替代方案。作为额外的方法论贡献，我们还实现并基准测试了具有改进统计收敛性质的时间离散近似方案。我们使用这些方法计算连续零差检测的经典Fisher信息，并证明它们在耗散临界点附近能够高效地获取该量，从而扩展了现有方法的适用范围。
英文摘要
Dissipative phase transitions in the driven-dissipative Kerr parametric oscillator offer a promising route for realizing criticality-enhanced quantum sensing based on continuous measurements. However, achieving such enhancement through realistic measurement schemes remains an outstanding challenge. Here, we extend the backaction-evasion strategy introduced in our earlier work for the Gaussian linear case [arXiv:2511.22248 (2025)] to analyze how the quantum and classical Fisher information scale with the Kerr nonlinearity at dissipative critical points. Our results show that backaction-evading homodyne monitoring achieves enhanced photon-number scaling that surpasses the standard quantum limit, and significantly outperforms alternative protocols such as continuous photon counting. As an additional methodological contribution, we also implement and benchmark time-discrete approximation schemes with improved statistical convergence properties. We use these methods to compute the classical Fisher information for continuous homodyne detection, and demonstrate that they provide efficient access to this quantity near dissipative critical points, thereby extending the reach of existing methods.
Comments15 pages, 4 figures, 1 table
