19. September 2022
New publi­ca­tion by Karl Leo
© Hector Fellow Academy

Paper by Karl Leo published in journal Advanced Materials

A team of physi­cists and chemists from the TU Dresden, includ­ing Hector Fellow Karl Leo, direc­tor of the Insti­tute of Applied Physics (IAP) and the Integrated Center for Applied Physics and Photonic Materi­als (IAPP), present an organic thin-film sensor that can be used for light source analy­sis and anti-counter­feit­ing appli­ca­tions. It describes a completely new way of wavelength identi­fi­ca­tion of light and one achieves a spectral resolu­tion below one nanome­ter. As integrated devices, the thin-film sensors could elimi­nate the need for exter­nal spectrom­e­ters in the future. The thin-film wavelength sensor has the advan­tage of being smaller and less expen­sive than commer­cial spectrometers.

Spectroscopy comprises a group of exper­i­men­tal techniques to decom­pose radia­tion accord­ing to a specific property, such as wavelength or mass. It is consid­ered one of the most impor­tant analyt­i­cal methods in research and indus­try. Spectrom­e­ters can deter­mine colors (wavelengths) of light sources and are used as sensors in various appli­ca­tions such as medicine, engineer­ing, food indus­try and many more. Commer­cially avail­able instru­ments are usually relatively large and very expen­sive. They are mostly based on the princi­ple of prism or grating: light is refracted and the wavelength is assigned accord­ing to the angle of refrac­tion. Due to its small size and cost, the new organic thin-film sensor has clear advan­tages over commer­cially avail­able spectrom­e­ters. "In addition to charac­ter­iz­ing light sources, the novel sensors can be used in anti-counter­feit­ing: The small and inexpen­sive sensors could be used, for example, to quickly and reliably check banknotes or documents for certain security features and thus deter­mine their authen­tic­ity, without the need for expen­sive labora­tory technol­ogy," explains Anton Kirch, doctoral researcher of the Insti­tute of Applied Physics (IAP).

A patent appli­ca­tion has already been filed for the new type of technology.

Congrat­u­la­tions Karl Leo!