Development of tunneling spectroscopy on Dirac electron system

为了研究在有机导体α-(BEDT-TTf)2I3中实现的狄拉克电子系统在压力下和在拓扑绝缘体Bi2Se_3表面上实现的特性，发展了磁场下的隧道光谱技术。作为结果，揭示了高质量载流子补偿的Bi2Se_3样品的合成方法和铜插层Bi2Se_3拓扑超导体的有力候选者，以及点接触法在上述材料上的隧穿光谱存在的问题。

In order to investigate features of Dirac electron system realized both in the organic conductor, α-(BEDT-TTF)2I3, under pressure and on the surface of the topological insulator, Bi2Se3, tunneling spectroscopy techniques under magnetic fields are developed. As the results, the synthetic methods for high-quality samples of carrier-compensated Bi2Se3, and a strong candidate for a topological superconductor, Cu-intercalated Bi2Se3, and problems of tunneling spectroscopy on the above materials by the point-contact method are revealed.