发表机构
Quaid-i-Azam University; Fatima Jinnah Women University; Ibnou Zohr University; COMSATS University Islamabad（奎德·阿扎姆大学; 法蒂玛·真纳女子大学; 伊本·佐赫尔大学; 科摩斯图斯伊斯兰堡大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究利用协方差矩阵方法，在耦合有损波导中研究高斯量子导引动力学，发现增加非经典性和压缩可增强导引，而损耗和纯度降低抑制导引，且非对称输入可实现方向可控的导引，为集成光子非对称量子信息协议提供平台。
AI 中文摘要
量子导引是一种重要的量子关联类型，在单侧设备无关（1SDI）量子信息协议中具有潜在应用。在本研究中，我们利用协方差矩阵形式，探索了耦合有损光波导中高斯量子导引的时间依赖动力学。我们明确引入了光学耗散，以考虑耦合波导中实际的传播损耗。我们系统地研究了输入高斯态的光学损耗率、纯度、非经典性和压缩对导引产生与演化的影响。结果表明，增加非经典性和压缩会增强高斯导引，而光学损耗和纯度降低则逐渐抑制导引。然而，在存在光学损耗的情况下，在有限的传播区间内仍可维持相当数量的导引。我们进一步考察发现，对于具有相同非经典性的输入态，导引是对称的，而非相等的非经典性则导致方向性导引不对称，这为通过输入态工程控制导引方向提供了一种途径。这些结果表明，耦合光波导在实际损耗条件下能够支持可控的高斯量子导引，并为非对称量子信息协议（包括1SDI量子密钥分发（QKD）和量子通信）提供了一个有前景的集成光子平台。
英文摘要
Quantum steering is an important type of quantum correlation with potential applications in one-sided device-independent (1SDI) quantum information protocols. In this contribution, we explore the time-dependent dynamics of Gaussian quantum steering in coupled lossy optical waveguides using the covariance matrix formalism. Optical dissipation is explicitly incorporated to account for realistic propagation losses in coupled waveguides. We systematically investigate the influence of the optical loss rate, purity, nonclassicality, and squeezing of the input Gaussian states on the generation and evolution of steering. The results demonstrate that increasing nonclassicality and squeezing enhances Gaussian steering, while optical loss and reduced purity progressively suppress it. However, a considerable amount of steering can persist over finite propagation intervals in the presence of optical loss. We further examine that steering is symmetric for input states with identical nonclassicality, while unequal nonclassicalities lead to directional steering asymmetry, offering a way to control the steering direction through input-state engineering. These results demonstrate that coupled optical waveguides can support controllable Gaussian quantum steering under practical loss conditions and offer a promising integrated-photonic platform for asymmetric quantum-information protocols, including 1SDI quantum key distribution (QKD) and quantum communication.
