A new photorefractive (PR) material sensitized with a novel functional unit DiPBI is prepared based on the guest/host approach. This unique mixture exhibits strong absorption in the whole range of visible light. Moreover, the photorefractive performance as well as PR speed is improved by far compared to the widely used sensitizer PCBM.

We incorporate a mixture of polystyrene (PS) and the highly conductive N, N-diphenyl-N, N-bis(3-methylphenyl)-[1, 1-biphenyl]-4, 4-diamine (TPD) as charge transporting agent into a photorefractive composite, wherein the liquid crystal 4-cyano-4-n-pentylbiphenyl (5CB) is the electro-optical unit and the perylene bisimide dimer DiPBI acts as sensitizing component. Investigation of the photocurrent reveals a strong enhancement of the photoconductivity. Compared to composites, wherein poly-n-vinylcarbazole (PVK) is the charge transporting agent, the internal photocurrent efficiency is enhanced 11 times. This dramatic improvement is attributed to an increase of charge generation and transport and it allows for a reduction of the applied electric field to get a photoconductivity that is comparable to PVK comprising composites.

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A novel dipolar-modulated charge-doped trilayer n-n organic heterojunction with a bidirectional tunable energy band discontinuity is constructed. The rectifying mechanism of the trilayer is similar to the rectifying and inverse-rectifying characteristics from n-p and p-n junctions, respectively. Zero-bias optoelectronic behavior and persistent photoconductivity are discovered. These results show that what are viewed as technological hurdles in the development of an organic n-n heterojunction should, in fact, lead to a better approach in organic optoelectronics.

The cover illustrates a photorefractive composite‐based, white light, multibeam coupler, wherein the novel broad‐band sensitizer DiPBI displaces the widely used PCBM. As the absorption spectrum of DiPBI stretches over the whole range of visible light, operation at any desired wavelength is possible. This essential advantage over PCBM makes the new compound a promising candidate for optical computing and colored 3D displays. , Z. Wang and co‐workers present this significant step towards the realization of such devices.