Combining Advanced Materials for Interface Engineering (CAMIE)

我们给自己设置的挑战是，基于我们独特的材料集成和界面控制方法，找到存储、操作和传输信息的全新方法。电子应用程序及其使用正在以指数级速度增长，信息和通信技术消耗的能源占全球能源消耗的6%。任何使用过电子设备的人都知道，它们很快就会变暖。但热量是他们使用电流的副产品，电流被不可持续地倾倒到环境中。电流被用来传输、存储、检索和执行操作。随着设备变得更小，问题就会增加，因为材料对电流的阻力更大，产生的热量也更多。这个问题的规模是巨大的。例如，谷歌报告称，大量能源被用来冷却他们的服务器群。2021年，他们使用了~12TWr的电力，与一个小国的用电量大致相同，而且这一趋势还在增加。互联网目前的碳足迹大于航空业，预计从2020年到2025年将翻一番。为了长期的可持续性，我们必须减少信息和通信技术的能源消耗。自旋电子学利用电子(自旋)的磁性进行应用。它为新设备提供了令人信服的可能性，这些设备可能会以更低的能耗运行。纯自旋电流在不转移电荷的情况下转移自旋，因此信息可以在没有电荷电流产生的热量的情况下交换。在设备中使用电场可以比使用磁场有很大的优势，包括使用更少的能量，但通常情况下，磁场不能被电场控制。分子界面可以被电场改变，铁电体的极化可以通过电转换，从而在连接时调整磁体的行为。取得进展的一个绊脚石是，这些不同的材料需要不同的制备技术，要用于ICT，它们必须很薄--厚度大约为几十个原子。这种薄层需要在制造过程中受到保护，然后将不同的层组合在一起。解决方案需要定制的设计和材料科学的突破。罗伊斯研究所是EPSRC的一项关键投资(GB 2.35亿)，旨在“加速新材料系统的发明和采用，以应对全球挑战”，推动英国战略，以提高我们的竞争能力，不仅是在科学方面，而且是在市场上。在利兹，我们最近安装了罗伊斯沉积系统：一套2200 GB的腔室，每个腔室都设计用于生长不同类型的先进材料，这些材料需要不同的沉积方法和环境进行处理。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免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，我们可以生长不同材料的层，并将它们结合在一起形成单一的混合结构。例如，我们可以：通过电极化形成二维材料来控制磁体；构建分子薄膜界面，从而实现可调谐的新兴磁、光电和超导特性；利用拓扑材料的自旋电流驱动磁性织构等。对这些混合结构的全面了解将为开发可利用的技术铺平道路，其中最初的好处将是以更少的能源实现信息处理和存储，减少碳排放，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.