Combining Advanced Materials for Interface Engineering (CAMIE)

我们为自己设定的挑战是，基于我们独特的材料集成和界面控制方法，找到从根本上存储、操作和传输信息的新方法。电子应用及其使用正以指数级速度增长，ICT消耗了全球6%的能源。任何使用过电子产品的人都知道，它们很快就会变暖。但热量是他们使用电流的方式的副产品，这种方式不可持续地排放到环境中。电流用于传递信息、存储信息、检索信息和执行操作。随着设备变得越来越小，问题也越来越严重，因为材料对电流的抵抗力越来越强，产生的热量也越来越多。这个问题的规模是巨大的。例如，谷歌报告说，大量的能源被用于冷却他们的服务器群。在2021年，他们使用了约12太瓦时的电力，大约相当于一个小国家，而且这个趋势还在增加。目前，互联网的碳足迹比航空业的碳足迹还大，预计从2020年到2025年将翻一番。为了长期的可持续性，我们必须减少信息通信技术的能源消耗。自旋电子学利用电子的磁性（自旋）进行应用。它为可能以更低的能量运行的新设备提供了令人信服的可能性。纯自旋电流传递自旋而不传递电荷，因此信息可以在没有电荷电流产生热量的情况下交换。在设备中使用电场比磁场有很大的优势，包括使用更少的能量，但通常磁场不能被电场控制。分子界面可以被电场改变，铁电体具有可以电切换的极化，因此当它们连接在一起时可以调整磁铁的行为。阻碍进步的一个障碍是，这些不同的材料需要不同的制备技术，而且要想在ICT中发挥作用，它们必须很薄——只有几十个原子那么厚。这种薄层在制造过程中需要受到保护，然后将不同的层组合起来。解决方案需要定制设计和材料科学的突破。罗伊斯研究所是EPSRC的一项重要投资（2.35亿英镑），旨在“加速新材料系统的发明和采用，以应对全球挑战”，推动英国的战略，提高我们的竞争力，不仅在科学领域，而且在市场上。在利兹大学，我们最近安装了罗伊斯沉积系统：这是一套价值220万英镑的房间，每个房间都是为了生长不同类型的先进材料而设计的，这些材料需要不同的沉积方法和处理环境。这些腔室通过超高真空管连接在一起，因此样品可以在转移的同时不受大气和杂质的影响。至关重要的是，通过在原子水平上控制它们的界面，我们可以生长出不同材料的层，并将它们组合成一个单一的混合结构。例如，我们可以：用电极化形成二维材料来控制磁铁；构建分子薄膜界面，导致可调谐的紧急磁，光电和超导性能；利用拓扑材料等的自旋电流驱动磁性织构。对这些混合结构的全面了解将为可开发的技术铺平道路，其中最初的好处将使信息处理和存储使用更少的能量，减少碳排放并延长电池寿命。我们的方法有可能影响许多技术领域，如数据存储、传感器、能量存储和量子材料。

The challenge we have set ourselves is to find fundamentally new ways to store, manipulate and transport information based on our unique approach to materials integration and interface control.Electronic applications and their use are increasing at exponential rates with 6% of the global energy consumed by ICT. As anyone who has used an electronic gadget knows, they rapidly get warm. But the heat is a by-product of the way that they use electric currents which is unsustainably dumped into the environment. Electric currents are used to transfer information, to store it, retrieve it and to perform operations. As devices become smaller, the problem increases because the materials become more resistive to currents and generate more heat. The scale of the problem is huge. As an example, Google reports that significant amounts of energy are used to cool their server farms. In 2021, they used ~12 TWhr of electricity, about the same as a small country, and the trend is increasing. The internet currently has a carbon footprint that is larger than that of the airline industry and is predicted to double from 2020 to 2025. For long-term sustainability we must reduce the consumption of energy in ICT. Spintronics exploits the magnetic property of electrons (spin) for applications. It offers compelling possibilities for new devices that might function at reduced energy. Pure spin currents transfer spin without transferring charge so that information can be exchanged without the heat a charge current generates. Using electric fields in devices can have great advantages over magnetic fields, including using less energy, but usually magnetism cannot be controlled by electric fields. Molecular interfaces can be altered by electric fields and ferroelectrics have a polarisation that can be switched electrically hence tuning the behaviour of a magnet when they are connected. A stumbling block to progress is that these different materials require different techniques of preparation and to be useful in ICT they must be thin - of the order of tens of atoms thick. Such thin layers need to be protected during their fabrication and then the different layers combined. The solution requires bespoke designs and breakthroughs in materials science. The Royce Institute is a key EPSRC investment (£235M) founded to "accelerate the invention and take-up of new material systems that will meet global challenges", driving the UK strategy to increase our ability to compete, not only in science, but in the marketplace. At Leeds we recently installed the Royce Deposition System: a £2.2M suite of chambers each of which is designed to grow a different type of advanced material that requires different deposition methods and environments for processing. The chambers are connected together through ultra-high vacuum tubes so samples can be transferred whilst being protected from the atmosphere and impurities. Crucially, by controlling their interfaces at the atomic level we can grow layers of different materials and bring them together into a single hybrid structure. For example, we can: form 2 dimensional materials with electrical polarisation to control magnets; build molecular thin film interfaces that lead to tuneable emergent magnetic, optoelectronic and superconducting properties; drive magnetic textures using spin currents from topological materials, etc. A complete understanding of these hybrid structures will pave the way to exploitable technology where the initial benefits will enable information processing and storage with less energy, reducing carbon emissions and prolonging battery life. Our approach has the potential to impact many areas of technology such as data storage, sensors, energy storage, and quantum materials.