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arXiv · 2402.09375

Local work-function manipulation by external optical stimulation

Jan Böhnke·Beatrice Andres·Larissa Boie·Angela Richter·Cornelius Gahl·Martin Weinelt·Wibke Bronsch
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Abstract

Strongly differing static dipole moments of the trans and cis isomers of photochromic azobenzene allow for optical switching the work function of azobenzene-functionalized self-assembled monolayers (SAMs). We apply these properties in a fundamental experiment to manipulate the area size of the switched SAM. Azobenzene molecules were excited by ultraviolet laser illumination and the transient isomerization profile of the SAM was spatially resolved recording photoemission electron microscopy (PEEM) images. Thereby we demonstrate the spatial tuning of the SAM work-function and discuss the role of the laser spot-profile in generating sharp edges or gradual changes of the work function.

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Jan Böhnke, Beatrice Andres, Larissa Boie, Angela Richter, Cornelius Gahl, Martin Weinelt, Wibke Bronsch. 2024-02-14. Local work-function manipulation by external optical stimulation. https://arxiv.org/abs/2402.09375

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