EAGER: SUPER: Carbon-based Superconductors Stable at Ambient Temperature and Pressure

非技术总结超导体--在地球表面条件下无电阻导电的材料--的存在将彻底改变从电网到计算和通信的各种技术。已经发现了在室温或接近室温时表现出超导电性的新材料，但它们只有在非常高的压力下才是稳定的，例如在地心内发现的。最大的挑战，无论是从根本上还是最终的应用，都是在环境压力下稳定这些和相关的超导材料。该项目由美国国家科学基金会材料研究部支持，通过综合理论计算和实验来审查以前未探索的化学成分，重点是富碳材料，以应对这一挑战。指导性的假设是，碳具有钻石的成键性质的结构可以在常压下导致室温超导。通过在高压和高温下合成，结合同时表征和复杂的计算来解释和指导实验，系统地探索了富碳化合物。该项目涉及对伊利诺伊大学芝加哥分校(UIC)不同人群的本科生进行教育和培训。这项研究的成功将导致基础科学的重要进展，创造技术重大变革的可能性，并培养下一代科学家，包括在STEM领域代表不足的群体。技术总结寻找在环境条件附近表现出超导临界温度的材料一直是凝聚态物理长期追求的目标，其中可能是量子信息技术的关键。在使用密度泛函理论对目标化学成分进行越来越准确的预测的指导下，高压实验证明了富氢材料在创纪录的高温下存在超导电性。其中一些材料中的氢被碳取代预计会在减压时可以保存的结构中产生高临界温度，这是因为它们的刚性碳骨架在环境条件下提供了动力学稳定，就像钻石一样。该项目在材料研究司的支持下，将由UIC的一个跨学科小组参与，以加速探索富碳相，从含轻碱金属的材料开始，利用加热和加压的原位x射线衍射法，测量超导电性，以及在常压或接近常压的情况下测试动力学稳定性。这些实验与DFT和其他理论计算相结合，并由其他理论计算提供信息，并通过机器学习方法和其他大数据技术进行增强。UIC小组在大学课程中纳入了项目中制定的方法。UIC是一家少数族裔服务机构，来自不同学生群体的本科生参与了这项研究和教育体验。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

NON-TECHNICAL SUMMARYThe existence of superconductors - materials that conduct electricity without resistance - at conditions of the Earth’s surface would revolutionize diverse technologies ranging from the electrical grid to computing and communications. New materials displaying superconductivity at or near room temperature have been discovered but they are stable only at very high pressures, such as found within the core of the Earth. The paramount challenge, both fundamentally and for eventual applications, is stabilizing these and related superconducting materials at ambient pressure. This project, supported by the Division of Materials Research at NSF, addresses this challenge through integrated theoretical calculations and experiments to examine previously unexplored chemical compositions, with a focus on carbon-rich materials. The guiding hypothesis is that structures in which carbon has the bonding properties of diamond could lead to room-temperature superconductivity at ambient pressure. Carbon-rich compounds are systematically explored using synthesis at high pressures and temperature in combination with both simultaneous characterization and sophisticated computations to interpret and guide the experiments. The project involves education and training of undergraduate students from the diverse population of the University of Illinois at Chicago (UIC). The success of this research would lead to important advances in basic science, create potential for major shifts in technology, and train the next generation of scientists, including groups underrepresented in STEM fields.TECHNICAL SUMMARYThe quest for materials that exhibit superconducting critical temperatures near ambient conditions has been a long-sought goal of condensed matter physics, which among others, could be key to quantum information technology. Guided by increasingly accurate predictions of targeted chemical compositions using density functional theory, high-pressure experiments have demonstrated the existence of superconductivity at record high temperature in hydrogen-rich materials. Replacement of hydrogen with carbon in some of these materials is predicted to give rise to high critical temperature in structures that can be preserved on decompression, owing to their rigid carbon frameworks, which impart kinetic stabilization at ambient conditions, much like for diamond. This project, supported by the Division of Materials Research, will involve an interdisciplinary team at UIC to carry out an accelerated exploration of carbon-rich phases, beginning with light alkali metal-containing materials, using in situ x-ray diffraction with heating and pressurization, measurements of superconductivity, and tests of kinetic stability at or near ambient pressure. The experiments are integrated with and informed by DFT and other theoretical calculations, augmented by machine learning approaches and other large data techniques. The UIC group incorporates the approaches developed in the project in university courses. Undergraduates from the diverse student population of UIC, a minority serving institution, take part in this research and education experience.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.