Electroluminescent transistors activated by optical stimuli

News

23/04/19

By creating organic electroluminescent transistors that respond to optical stimuli, Paolo Samorì and his team have taken a new step in the production of multifunctional optoelectronic devices. The discovery, made in collaboration with University College London and Humbolt University Berlin as part of the European iSwitch project, was published in Nature Nanotechnology.

"A remote control is an object with several buttons, each of which is associated with a television feature," says Paolo Samorì, director of the Institute of Supramolecular Science and Engineering, specialising in nanochemistry. Since 2005, the researcher has been working on reproducing this multifunctional aspect in optoelectronic devices at the nanoscopic and microscopic scale.

To develop these systems with sophisticated properties, researchers use organic molecules with different properties that they try to activate using various external stimuli (optical, magnetic, electrochemical, etc.) "The whole question is how to assemble them so as not to lose their individual properties, without forgetting how to be able to simultaneously activate them independently”.

Smart sensors

A new step has been taken with the development of electroluminescent transistors responding to optical stimuli. "We can activate and deactivate the light emission of the active material that makes up the transistor using two lasers, one ultraviolet and the other green, and thus emit red, blue or green light at the micrometre level. This revolutionary method can produce screens with a resolution more than 3,000 times better than the most powerful "Retina" screens.

Light emitting diodes being the basis of many optoelectronic devices, this research could be used for the production of flexible materials, and also for the development of smart sensors. "Clothing could, for example, detect light at certain wavelengths, to know the level of environmental pollution, sunshine, the presence of bacteria, etc. Even though there is still an enormous stride between laboratory discovery and technology”.

Marion Riegert

*Set of techniques and devices that link optics and electronics.