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Metal-induced gap states in epitaxial organic-insulator/metal interfaces

Manabu Kiguchi·Ryotaro Arita·Genki Yoshikawa·Yoshiaki Tanida·Susumu Ikeda·Shiro Entani·Ikuyo Nakai·Hiroshi Kondoh·Toshiaki Ohta·Koichiro Saiki·Hideo Aoki
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Abstract

We have shown, both experimentally and theoretically, that the metal-induced gap states (MIGS) can exist in epitaxially grown organic insulator/metal interfaces. The experiment is done for alkane/Cu(001) with an element-selective near edge x-ray absorption fine structure (NEXAFS), which exhibits a pre-peak indicative of MIGS. An {\it ab initio} electronic structure calculation supports the existence of the MIGS. When the Cu substrate is replaced with Ni, an interface magnetism (spin-polarized organic crystal at the interface) is predicted to be possible with a carrier doping.

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Manabu Kiguchi, Ryotaro Arita, Genki Yoshikawa, Yoshiaki Tanida, Susumu Ikeda, Shiro Entani, Ikuyo Nakai, Hiroshi Kondoh, Toshiaki Ohta, Koichiro Saiki, Hideo Aoki. 2004-08-31. Metal-induced gap states in epitaxial organic-insulator/metal interfaces. https://doi.org/10.1103/physrevb.72.075446

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