Abstract
Diarylethenes are known as thermally stable photo-chromic compounds, particularly of which diarylethene derivatives having bithiophene as the side groups undergo the great change in the π-electron conjugation length between the open-form and closed-form upon their photo-isomerization. Consequently, the ionization potential (Ip) is expected to change between both forms. In this paper, we have applied the difference of Ip between these two forms for controlling the hole injection from a metal electrode to an organic film. We have succeeded in demonstrating the photo-switch of the injection current on the order of sub-miliampare upon photo-isomerization by inserting a thin film of diarylethene derivative in-between metal and organic charge transport layer.
