Transient biphotonic optical storage in the guest−host system 4-amino-4‘-nitroazobenzene/polycarbonate is accomplished by excitation of the azo dye molecules at 488 nm with an argon ion laser and subsequent writing at 633 nm with two interfering HeNe laser beams. The mechanism of the observed refractive index change is investigated by detailed kinetic studies. It is based on the formation of cis isomers of the azo dye by the argon ion laser. These are subsequently transformed back to the trans isomers by fast photoinduced cis−trans isomerization where the interference of the writing beams is constructive and by slow thermal cis−trans isomerization where the interference of the HeNe beams is destructive, respectively. The cis concentration produced by the exciting light is thus modulated with the HeNe beams, resulting in a modulation of the refractive index.

In this work, discrepancies between measured single-molecule linewidth distributions and distributions simulated with the standard tunneling model in the sudden-jump approximation are studied for terrylene and di-tert-butylterrylene dopant molecules in poly(vinylbutyral). The experimental data has been carefully checked for systematic errors. It is shown that the results are in disagreement with the standard model, but that the incorporation of a distribution of molecule−polymer coupling strengths would remove this disagreement. Additionally, the experimental observation of a surprising correlation between the single-molecule line areas and the matrix−molecule interaction strength is presented, and a hypothesis is put forward for its physical origin.

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Summary: The success of automated and parallel drug‐discovery workflows in pharmaceutical research has sparked similar developments in materials science. This contribution provides an overview of published high‐throughput experimentation work in the area of polymeric coatings and thin films. Methodological aspects, experimental examples, and remaining challenges are discussed.Robotic system (GE) for crosshatch application.magnified imageRobotic system (GE) for crosshatch application.

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