Theoretical Investigations in Superconductivity and Graphene

超导是一种发生在接近绝对零度（-273C）的极低温度下的现象，在这种温度下，某些材料失去了对电流流动的所有电阻，成为完美的导体。自1911年首次被发现以来，超导性一直在为物理和材料研究界提供重大的理论和实验挑战。近年来，新型超导体以惊人的速度被发现。1986年，一项重大突破出现了，发现了一类新的材料，它们的超导温度比以前已知的要高得多。这在世界各地的科学家中动员了前所未有的活动，因为利用超导的应用和改进现有应用的潜力，例如日本正在实施的高速磁悬浮列车，用于电力传输的超导电缆，用于通信的微波滤波器，工业磁铁和医学诊断的MRI（磁共振成像）。这些新的超导体中有许多是非常非常规的，对传统的超导理论提出了独特的困难，可能需要一个新的范例。对这些材料的研究不仅将为如何开发新材料和改善应用性能提供指导，而且还将为基础科学带来新的见解。我进行了理论超导的研究，以进一步了解传统和非常规超导体中的这种现象。我的工作重点有三个方面：1)计算超导体的性质，与实验进行比较；2)为研究超导体的实验组提供理论支持；3)研究阐明新型超导体（如高温超导体）超导性质的新机制。随着最近石墨烯的发现，单片碳原子具有可能影响微电子和光电子学的奇异性质，我计划研究石墨烯和相关系统的光学性质和超导性的潜力。

Superconductivity is a phenomenon occuring at very low temperatures approaching absolute zero (-273C) where certain materials lose all resistance to the flow of electrical current and become perfect conductors. First discovered in 1911, superconductivity continues to provide major theoretical and experimental challenges to the physics and materials research communities. In recent times, new classes of superconductors have been discovered at a phenomenal rate. A major breakthrough came in 1986 with the discovery of a new family of materials which superconduct at much higher temperatures than previously known. This mobilized an unprecented activity among scientists around the world due to potential for applications and improvements in existing applications using superconductivity, such as the high speed MAGLEV (Magnetic Levitation) train being implemented in Japan, superconducting cables for power transmission, microwave filers for communications, industrial magnets, and medical diagnosis with MRI (Magnetic Resonance Imaging). Many of these new superconductors are highly unconventional, posing unique difficulties with the conventional theory of superconductivity, and likely will require a new paradigm. It is expected that study of these materials will not only provide guidance as to how to develop new materials and improved properties for applications, but will also lead to new insights in to fundamental science. I have carried out research in theoretical superconductivity to further understanding of this phenomenon in both conventional and unconventional superconductors. The focus of my work is three-fold: 1) to calculate properties of superconductors for comparison with experiment; 2) to provide theoretical support for experimental groups studying superconductors; 3) to study new mechanisms for elucidating the nature of superconductivity in novel exotic superconductors, such as the high temperature superconductors. With the recent discovery of graphene, a single sheet of carbon atoms with exotic properties which may impact micro- and optoelectronics, I plan to study the optical properties and the potential for superconductivity in this and related systems.