Elasto-superconductivity: a pathway to devising new unconventional superconductors

超导性是在某些材料和足够低的温度下电阻率降低到零。它广泛用于高功率应用和极端磁场-例如，医疗保健中的MRI/NMR机器，高输出风力涡轮机和磁悬浮高速列车。全球超导体市场目前估计超过55亿英镑，预计到未来十年将翻一番。超导性是量子力学在大尺度上的显着表现，并支撑着一些最令人兴奋的技术可能性。其中之一是新兴的量子计算领域，其中最有前途的原型是基于固态超导芯片。然而，超导性是一种微妙的状态：它需要低温，并限制周围的磁场。许多具有强超导性的已知材料具有困难的机械性能。因此，超导材料的优化有巨大的空间，具有巨大的技术和经济效益。更实用的高温超导体最有希望的候选者是所谓的“非常规”超导体，其中许多电子之间强烈而复杂的相关性引起特别强大的超导性。它们可能最终提供一条通向室温超导性的途径。然而，我们控制高温超导性的能力仍然非常有限。其中一个主要挑战是复杂性：电子之间的强烈相互作用往往会导致它们以其他方式排列，例如形成电荷密度波。在强相互作用的电子可以形成的许多结构中，尚不清楚哪些与超导性有关。在这个项目中，我们通过对非常规超导性关键方面的材料进行实验，并设计计算来预测复杂的相关系统的性质，以保证准确性，来解决这个问题。我们利用最近取得的巨大进展，精确的数值方法的相关电子系统，以制定具体的条件，实现所需的性能。这些计算将通过本提案实验部分的结果进行验证，并反过来产生可通过实验验证的假设。这里采用的实验方法是对样品施加极大的压力，以扭曲它们的晶格。这种方法已经被证明是非常强大的：在高压下，许多材料的电子特性与未加压的材料有很大的不同，实际上它们可以被认为是新材料。我们的研究结果将提供对有利于强大超导性的关键条件的深入了解，并允许开发用于可再生能源和量子计算等应用的改进材料。

Superconductivity is a decrease of the electrical resistivity to zero, in certain materials and at sufficiently low temperature. It is widely employed for high-power applications and extreme magnetic fields - for example, in MRI/NMR machines in healthcare, in high-output wind turbines, and in magnetically-levitated high-speed trains. The global superconductor market is currently estimated at over £5.5B, and is expected to double by the next decade. Superconductivity is a remarkable manifestation of quantum mechanics on large length scales, and underpins some of the most exciting technological possibilities. One of them is the emerging field of quantum computation, in which the most promising prototypes are based on solid-state superconducting chips. However, superconductivity is a delicate state: it requires low temperatures, and limits on the ambient magnetic field. Many known materials with robust superconductivity have difficult mechanical properties. There is therefore enormous scope for optimisation of superconducting materials, with huge technological and economic benefits. The most promising candidates for a more practical high-temperature superconductor are the so-called "unconventional" superconductors, in which strong and complex correlations between many electrons induce particularly robust superconductivity. They may ultimately provide a route to room-temperature superconductivity. However, our ability to control high-temperature superconductivity has remained severely limited. One of the main challenges is complexity: the strong interactions among electrons often cause them to order in other ways, such as into ribbons of charge known as charge density waves. Of the many structures that strongly-interacting electrons can form, it is unclear which are related to the superconductivity.In this project, we take on this problem through a combination of experiments on materials that isolate key aspects of unconventional superconductivity, and calculations designed to predict properties of complex, correlated systems with guaranteed accuracy. We take advantage of the dramatic recent progress of precision numerical methods for correlated electron systems, in order to formulate specific conditions for achieving desired properties. These calculations will be validated by results from the experimental portion of this proposal, and in turn will generate hypotheses that are testable experimentally. The experimental method to be employed here is to apply extremely large pressures to samples, in order to distort their lattices. This method has proved to be very powerful: under high pressure, the electronic properties of many materials differ so much from the unpressurised material that they can be considered, in effect, as new materials. Our results will provide insight into the key conditions that favour robust superconductivity, and allow development of improved materials for applications such as in renewable energy and quantum computation.