MeVQE: A world-leading centre for MeV scale entanglement physics

该方案汇集了来自强子物理、核伽马射线能谱、等离子体物理和量子信息领域的研究人员组成的跨学科联盟。它将使英国在许多开创性的基本测试和光子量子纠缠应用方面处于领先地位，这些测试和应用主要是在很大程度上未被探索的兆电子伏特(MeV)能量尺度，通常被称为“伽马光子”。通过在快速、经济高效和高质量的伽马光子探测系统中使用最新的量子技术，促进了对纠缠的测量和对这一区域的利用。在这种MeV尺度上，可以获得医学成像和国土安全方面的新的和令人兴奋的可能性，这些可能性目前是更广泛研究的光学制度所无法企及的。电子的反粒子(正电子)的湮灭提供了能量约为0.5 MeV的量子纠缠光子的来源。用最新的量子技术测量这些光子，可以提取出清晰的量子纠缠签名(或见证)，与传统技术相比，在精度和统计方面都有很大的变化。光子的量子纠缠导致了“诡异”(根据爱因斯坦的说法！)距离效应-测量一个光子的可观测性(例如，它的偏振、位置)会即时影响另一个光子的相互作用方式，即使它们在空间上完全分开。根据我们目前的理论，这种联系永远不会减弱，甚至延伸到宇宙的大小！然而，尽管量子理论在小尺度(例如原子、原子核、粒子)上工作得非常好，但我们知道它是不完整的(例如，它不包括引力)，所以建立量子理论的有效性，以描述大尺度上的纠缠，以新的精度水平，在不断增加的距离，在大量的伽马波长上，在加速标架(重力相当于爱因斯坦广义相对论中的加速度)，在更高的光子能量，在运动标架(根据爱因斯坦的狭义相对论)，以及在缩小波包大小都是重要的和基本的测试。该联盟将提供使用最新的探测器量子技术、尖端等离子体加速器方法和来自世界上最强粒子束设施之一的数据集获得的突破性新数据。这些数据将被解释为第一个实现MeV级纠缠的模拟。此外，除了纯科学，通过对MeV级纠缠的新水平的理解而实现的应用，对社会有许多令人兴奋的潜在好处。例如，如果您在医院进行正电子发射断层扫描(PET)，检测到的伽马光子是量子纠缠的，但我们只是刚刚了解这些额外信息的好处和影响。我们的工作将提供关键数据，以指导未来更高质量和更具成本效益的扫描仪的发展。MEV尺度的光子具有在大量物质中传播的非常有用的能力，而纠缠的好处还没有被探索出来。我们对MeV级纠缠的发展可能对新的安全扫描设备具有重要的意义，例如在港口和机场。纠缠在下一代紧凑型激光-等离子体粒子加速器中的作用也将被确立，这些技术在未来的医疗中具有巨大的潜力，以及用于纯科学的下一代粒子加速器的潜在技术。

This programme brings together an interdisciplinary consortium of researchers from the hadron physics, nuclear gamma ray spectroscopy, plasma physics and quantum information fields. It will enable UK leadership in a number of pioneering fundamental tests and applications of photon quantum entanglement in the largely unexplored Mega electronVolt (MeV) energy scale, often referred to as "gamma-photons". Measurement and exploitation of entanglement into this regime is facilitated by employing the latest quantum technologies in fast, cost effective and high-quality gamma-photon detection systems. At this MeV scale new and exciting possibilities in medical imaging and homeland security can be accessed which are currently out of reach from the more extensively studied optical regime. The annihilation of the antiparticle of the electron (the positron) provides a source of quantum-entangled photons with energy around 0.5 MeV. Measuring these photons with the latest quantum technologies allows clear signatures (or witness) of quantum entanglement to be extracted, with a step change in precision and statistics compared to conventional technologies. The quantum-entanglement of the photons results in the "spooky" (according to Einstein!) action at a distance effects - measurement of an observable for one of the photons (e.g. its polarisation, location) instantaneously affects how the other interacts, even if they are well separated spatially. According to our current theories this connection never diminishes, extending out even to the size of the universe! However, although quantum-theory works incredibly well at the small scale (e.g atoms, nuclei, particles) we know it is incomplete (e.g. it doesn't include gravity) so establishing the validity of the quantum-theory to describe entanglement at large scales with new levels of precision, at increasing distance, over large numbers of gamma wavelengths, in accelerating frames (gravity is equivalent to acceleration in Einstein's general theory of relativity), at higher photon energies, in moving frames (with Einstein's special relativity), and at reducing wavepacket size are all important and fundamental tests. The consortium will provide groundbreaking new data obtained with the latest detector quantum-technologies, cutting edge plasma accelerator methods and a dataset from one of the world's most intense particle beam facilities. The data will be interpreted with the first implementation of MeV-scale entanglement into simulation. Furthermore, alongside the pure science, applications enabled by a new level of understanding of MeV-scale entanglement have many exciting potential benefits to society. For example, if you have a Positron Emission Tomography (PET) at a hospital the detected gamma photons are quantum entangled, but we are only just learning of the benefits and impacts of this additional information. Our work will deliver the key data to guide future development of higher quality and more cost effective scanners. MeV-scale photons have the very useful ability to travel through large amounts of material and the benefits of entanglement are unexplored. Our developments of MeV-scale entanglement may have important implications for new security scanning devices e.g. at ports and airports. The role of entanglement in next generation compact laser-plasma particle accelerators will also be established, technologies which have tremendous potential in future medical treatments as well as a potential technology for next-generation particle accelerators for pure science.