非高斯条件下的量子照明研究

Quantum illumination, namely, quantum target detection, is a new direction towards the detection and identification of object hidden in strong noisy environment. Compared with conventional classic target detection, the essence of quantum illumination is to detect the potential target with two mode quantum entangled state. For a given transmitted energy, the quantum illumination can achieve a target-detection probability of error much lower than the illumination scheme without entanglement. During our previous study, we find that the quantum illumination with photon subtracted (PS) two mode squeezed state and the result shows that PS could further reduce the probability of error, extend the regime in which quantum illumination surpass to classical illumination and improve its robustness against photon loss. The aim of this proposal is to continue our research on quantum illumination with non-Gaussianity. Our study will cover the choice and preparation of entanglement state, the transmission of entanglement and the detection of entanglement. To be specific: (1) We will investigate the feasibility of quantum illumination with Gaussian and non-Gaussian multi-mode entangled state, giving an optimization of the signal source. (2) We will study the transmission of entanglement through fluctuating medium and give a thorough evaluation of the feasibility of quantum illumination in atmospheric turbulence environments. (3) We will investigate the possibility of further improving quantum illumination with non-Gaussian post-processing of collected entanglement. These post-processing will include typical entanglement distillation and noiseless linear amplification as well, which was assumed to be helpful for improving the correlation of post-processed state, reducing the probability of mistaken discrimination and finally improving the applicability of realistic quantum illumination.

量子照明，准确地说是量子目标探测。它是量子信息技术与传统目标探测与识别相交叉的新兴研究方向。与传统目标探测相比，量子照明是用两模或多模纠缠量子态进行暗弱目标的探测。在探测信号能量相同的条件下，基于量子纠缠态的量子照明具有更低的误判概率。我们研究证明了光子擦除技术可以进一步降低虚警概率、扩展量子照明的适用范围、提高在光子有损环境下的量子照明的整体性能。本项目拟围绕非高斯条件下的量子照明，从纠缠信号的制备、传输和探测三个角度进行研究。具体地：(1)研究基于多模高斯和非高斯纠缠态的量子照明方案，解决纠缠光源的优化和改进问题。(2) 研究随机介质条件下非高斯信道中量子态的动力学模拟，解决大气湍流条件下的量子照明性能评估问题。(3)研究以纠缠蒸馏和无噪线性放大为代表的量子非高斯后处理操作，提高量子照明接收端的纠缠态中的量子关联，进一步降低虚警概率，提升量子照明的实用性水平。

量子照明，准确地说是量子目标探测。它是量子信息技术与传统目标探测与识别相交叉的新兴研究方向。与传统目标探测相比，量子照明是用两模或多模纠缠量子态进行暗弱目标的探测。在探测信号能量相同的条件下，基于量子纠缠态的量子照明具有更低的误判概率。我们研究证明了光子擦除技术可以进一步降低虚警概率、扩展量子照明的适用范围、提高在光子有损环境下的量子照明的整体性能。.本项目围绕非高斯条件下的量子照明，从非高斯纠缠态的制备、非高斯信道、以及非高斯的量子探测三个角度进行研究。截止目前，发表SCI论文8篇，其中Phys.Rev.A 、Optics Express、OSA Continuum、JOSA B各1篇。.具体地：.(1)研究基于光子注入的相干态量子雷达方案。设计了一种无两模压缩态输入的量子雷达探测方案。该方案可以同等条件下，将误判概率降低两个数量级。我们还讨论了多模非高斯纠缠态的量子照明方案，对光子数关联的多模纠缠在量子目标探测中的适用性问题进行了分析。.(2) 研究非高斯信道条件下量子纠缠的动力学。以大气湍流条件信道为例，研究了该非高斯信道下的量子纠缠蒸馏、量子隐形传态、量子密钥分发等问题，验证了非高斯信道下量子态输入输出关系。证明了非高斯信道下量子纠缠分发的可行性。我们还结合最近双场量子密码的成果，利用在中间进行非高斯探测的办法，研究了如何高效地分发纠缠相干态的问题。.(3)证明了局域位移操作可以确定性地提高量子照明的效果。我们以光子催化为突破口，证明了光子催化与量子无噪放大的等效性。证明了量子催化下量子态的相干性明显增强，可以进一步降低虚警概率，提升量子照明的实用性水平。.研究过程中我们也衍生出了任意多模高斯态光子数统计计算法。该算法可以更加深入地揭示了多模量子纠缠的光子数统计。这为我们研究连续变量多体纠缠及其演化提供了工具。我们将该工具应用到了强压缩条件下的纠缠蒸馏和强损耗下的纠缠分发理论中，取得了较好的效果。