Large Baseline Quantum-Enhanced Imaging Networks

成像和参数估计是大多数现代科学的基础，改进的成像技术的发展将在科学和文化方面产生极其广泛的影响。目前的成像技术受到孔径尺寸、损耗和系统噪声的限制，但最近的研究结果表明，采用量子计量技术可以克服衍射极限。量子增强计量学的实现需要大尺度纠缠态的可靠来源。然而，这种状态是非常脆弱的，很容易被环境噪声破坏。因此，量子增强传感的演示目前仅限于实验室环境。与此同时，物理学家正在构建越来越大的量子网络，并有望实现安全通信和分布式量子计算。量子网络提供了允许量子态从一个位置转移到另一个位置的资源，其中相位和幅度信息都被忠实地再现。将量子互联网的空间分离共享量子资源与大规模成像的要求相结合，我们可以设计出原则上实现成像分辨率更好许多数量级的协议。在这个理论提案中，我们开发了在量子网络上执行2D和3D成像和传感的最佳架构，能够通过专用的量子纠错协议减轻损耗和噪声。与此同时，我们将设计非相干成像处理方法，允许实现极大的基线，（例如，地球的直径或更大）。我们首先构建了高精度时间测量的理论，这为执行时钟同步和执行目标测距/检测提供了可能性。然后，我们建立远程站点之间的共享相位参考，允许在我们的成像孔径的远端收集的信号的相干处理。然后，我们将使用大型网络来执行成像，并通过量子纠错来集成损失和噪声保护。最后，我们探索了训练量子干涉仪用于热态和纠缠态的物体识别的方法。因此，该项目通过测量优化和状态优化（包括量子纠错）消除了当前成像和参数估计的局限性。该项目的宏伟目标是将量子成像、量子计量和量子通信联系起来，对整个量子技术领域产生深远影响。它提出了一个新的，统一的理论，大基线的二维和三维量子成像和计量学，将紧密结合的实验专业知识的大学昆士兰州（澳大利亚），埃尔兰根（德国），和布里斯托（英国）。其结果将带来低噪声探测器，高精度测量和超分辨率图像，并通过创新的实验设计实现。该系统将特别适合在高噪声环境中运行，应用于恒星干涉测量和测距;它们将直接影响英国将量子信息用于加密应用，导航系统，场传感器和通信技术。

Imaging and parameter estimation underpin most of modern science, and the development of improved imaging techniques will have an extremely broad impact, scientifically and culturally. Current imaging techniques are limited by aperture size, losses, and system noise, but recent results show that the diffraction limit can be overcome by employing techniques from quantum metrology. The realisation of quantum-enhanced metrology requires reliable sources of large-scale entangled states. However, such states are extremely fragile and are easily destroyed by environmental noise. As such, demonstrations of quantum-enhanced sensing are presently limited to a laboratory setting.Meanwhile, physicists are building ever-larger quantum networks, with the promise of secure communication and distributing quantum computing. Quantum networks provide resources that allow the transfer of quantum states from one location to another, where both phase and amplitude information is faithfully reproduced. Combining the spatially separated shared quantum resources of the Quantum Internet with the requirements of large-scale imaging, we can devise protocols that in principle achieve imaging resolution that is many orders of magnitude better. In this theoretical proposal we develop the optimal architecture for performing 2D and 3D imaging and sensing on a quantum network, with the ability to mitigate loss and noise via dedicated quantum error correction protocols. In parallel, we will devise incoherent imaging processing methods, allowing one to achieve extremely large baselines, (e.g., the diameter of the Earth or larger) at optical frequencies. We first construct the theory for high-accuracy time measurements, which opens up the possibility to perform clock synchronization and perform target ranging/detection. Then we establish shared phase references between distant sites, allowing coherent processing of signals collected at far ends of our imaging aperture. Then, we will use large networks to perform imaging, integrated with loss and noise protection via quantum error correction. Lastly, we explore methods to train a quantum interferometer for object recognition for both thermal and entangled states. Thus, the project removes the current limitations of imaging and parameter estimation by measurement optimisation, as well as state optimisation (including quantum error correction).This project has the ambitious goal of linking quantum imaging, quantum metrology and quantum communication, with a profound impact on the whole field of quantum technologies. It presents a novel, unified theory on large-baseline 2D and 3D quantum imaging and metrology that will be tightly combined with the experimental expertise of the Universities of Queensland (Australia), Erlangen (Germany), and Bristol (UK). The result will bring about low-noise detectors, highly accurate measurements, and super-resolved images, enabled by innovative experimental designs. The systems will be particularly suited to operate in a high-noise environment, with applications to stellar interferometry, and ranging; they will directly impact the UK's use of quantum information for cryptographic applications, navigation systems, field sensors, and communication technologies.