钾嵌入苝和蔻烯薄膜中费米能级处无光发射：结构、极化子还是关联物理？

Absence of photoemission from the Fermi level in potassium intercalated picene and coronene films: structure, polaron, or correlation physics?

机构信息

IFW Dresden, P. O. Box 270116, D-01171 Dresden, Germany.

出版信息

J Chem Phys. 2012 Apr 7;136(13):134503. doi: 10.1063/1.3699188.

Abstract

The electronic structure of potassium intercalated picene and coronene films has been studied using photoemission spectroscopy. Picene has additionally been intercalated using sodium. Upon alkali metal addition core level as well as valence band photoemission data signal a filling of previously unoccupied states of the two molecular materials due to charge transfer from potassium. In contrast to the observation of superconductivity in K(x)picene and K(x)coronene (x ~ 3), none of the films studied shows emission from the Fermi level, i.e., we find no indication for a metallic ground state. Several reasons for this observation are discussed.

摘要

采用光电子能谱研究了钾嵌入苉和蔻烯薄膜的电子结构。此外，还使用钠对苉进行了嵌入。碱金属的加入使得芯能级和价带光电子发射数据表明，由于钾的电荷转移，两种分子材料的先前未占据态被填满。与在 K(x)苉和 K(x)蔻烯（x~3）中观察到超导性不同，所研究的薄膜中没有一个显示费米能级的发射，也就是说，我们没有发现金属基态的迹象。讨论了观察到这种情况的几个原因。