EAPSI:Investigation of the Unconventional Superconducting Mechanism in Li0.9Mo6O17

新材料的发现和理解推动了计算机时代的技术发展。对半导体特性的研究为现代计算机电子学奠定了基础。对金属和绝缘体的更好理解使微制造和节能技术成为可能。超导体的发现给人们带来了无能量损失的电力转移的希望。该项目研究了一种奇异的超导材料Li0.9Mo6O17，由京都大学的松田友治教授领导，他是非常规超导体领域的领军人物之一。这种材料表现出一些不同寻常的低维性质，但人们对这些性质还没有很好的了解。这个项目将通过用尖端只有几个原子的尖端探测材料来阐明这些不寻常的性质。在非常寒冷的环境中，通过将电流通过针，可以揭示Li0.9Mo6O17的超导性质。更好地了解这种材料的性质将促进非传统超导体领域的发展，并有望对未来的电子学和计算产生影响。拟议的研究目的是确定准一维晶体Li0.9Mo6O17的超导机制。这种晶体被认为是一种鲁廷格液体，一种奇异的物质状态，其中电子分离为独立的电荷波和自旋波。许多人对Li0.9Mo6O17的正常态进行了研究，揭示了令人兴奋的新物理。然而，关于Li0.9Mo6O17的超导态仍有许多需要了解的地方。有证据表明Li0.9Mo6O17是一种非传统的自旋三重态超导体，但对超导带隙的详细研究将有助于阐明超导机制。在松田友治教授的指导下，PI将生长出高质量的Li0.9Mo6O17单晶，并在超导状态下进行扫描隧道显微镜(STM)。为了在超导状态下进行Li0.9Mo6O17的第一次STM测量，PI将使用3He制冷的STM。STM对超导带隙的研究将揭示Li0.9Mo6O17的行为是否符合非传统的自旋三重态超导电性或其他机制。该奖项由东亚和太平洋夏季学院计划资助一名美国研究生的夏季研究，由NSF和日本科学促进会共同资助。

The discovery and understanding of new materials has driven technology development in the computer age. Research on the properties of semiconductors has laid the foundation for modern computer electronics. Better understanding of metals and insulators has enabled micro-fabrication and energy efficient technology. The discovery of the superconductor has lead to the hope of power transfer without energy loss. This project investigates an exotic superconducting material, Li0.9Mo6O17, under one of the leading scientists in the field of unconventional superconductors, Professor Yuji Matsuda from Kyoto University. This material shows some unusual low-dimensional properties that are not well understood. This project will clarify those unusual properties by probing the material with a sharp needle, which has a tip consisting of only a few atoms. By running electricity through the needle in a very cold environment, the nature of superconductivity in Li0.9Mo6O17 can be revealed. Better understanding of this material's properties will lead to an advancement of the field of unconventional superconductors and has promise to impact the future of electronics and computing.The objective of the proposed research is to determine the superconducting mechanism of the quasi-1D crystal Li0.9Mo6O17. This crystal has been proposed to be a Luttinger Liquid, an exotic state of matter where the electrons separate into independent charge and spin waves. Many studies have been done on Li0.9Mo6O17 in the normal state revealing exciting new physics. However, there is still much to be learned about the superconducting state of Li0.9Mo6O17. There is some evidence suggesting that Li0.9Mo6O17 is an unconventional spin-triplet superconductor, but a detailed study of the superconducting gap, which would elucidate the superconducting mechanism, has not been done. The PI, under the mentorship of Professor Yuji Matsuda, will grow high quality single crystal Li0.9Mo6O17 and perform Scanning Tunneling Microscopy (STM) in the superconducting state. To perform the first STM measurements of Li0.9Mo6O17 in the superconducting state, the PI will employ STM with 3He refrigeration. An STM study of the superconducting gap will reveal if Li0.9Mo6O17 behaves according to unconventional spin-triplet superconductivity or some other mechanism.This award under the East Asia and Pacific Summer Institutes program supports summer research by a U.S. graduate student and is jointly funded by NSF and the Japan Society for the Promotion of Science.