中文摘要：

Mott金属-绝缘体相变（MIT）是凝聚态物理中的一个非常基本的概念.长期以来,Mott型MIT的概念被广泛应用于凝聚态物理的许多领域,特别是用于描述强关联系统的电子结构特征.然而到目前为止,完全由电子关联驱动的MIT并没有被观察到.因此,是否存在着完全由于电子之间的强关联效应导致的Mott型MIT一直是科学家们感兴趣的重要问题.近日,中国科学院物理研究所方忠研究员组、郭建东研究员组和美国Florida International大学的Jiandi Zhang教授研究组及美国Tennessee大学及橡树岭国家实验室的E.W.Plummer教授研究组、Rong Ying Jin教授研究组合作,通过实验与理论相结合的研究,在Ca1.9Sr0.1RuO4表面首次实现了纯电子驱动的Mott型MIT,发生电子结构相变时并没有相应的结构畸变出现.该研究成果对于人们认识电子-电子关联效应引起的Mott转变具有非常重要的意义.

英文摘要：

Mott metal-insulator transition （MIT） is a fundamental concept in condensed-matter physics. The related principles have been applied to many fields, especially to the description of electron characteristics in strongly-correlated systems. Although an inherent Mott-MIT is purely electronic in origin, in practice, it is almost always accompanied by a structural transition. Such a situation complicates the understanding of the basic mechanism of Mott-MIT. It is recently reported by Zhong Fang＇ s group and Jiandong Guo＇ s group in the Institute of Physics, Chinese Academy of Sciences, Jiandi Zhang＇ s group in Florida International University, E. W. Plummer＇ s group in the University of Tennessee, and Rongying Jin＇ s group in Oak Ridge National Laboratory that a purely electron-driven Mott-MIT is realized on the surface of Ca1. 9Sr0. 2 RuO4 without being accompanied by structural distortion.