Light switch

Although inorganic ambipolar transistors have been around for more than two decades, their organic counterparts, available only in recent years, could be used to make integrated photodetectors, electro-optical circuits and full-colour and monochromatic image sensor arrays.

Traditionally, ambipolar organic field-effect transistors (OFETs) were developed as electronic switches. But recently, OFETs with additional functionalities have also made their debut — the most notable examples being the light-emitting (LE-OFETs) and light-sensing (LS-OFETs) transistors.

Now, researchers from

and the

aim to design, develop and study such OFETs for use in a variety of different optoelectronic applications. In particular, they aim to demonstrate LS-OFETs with high photoresponsivity and fast switching characteristics.

If the researchers' work succeeds, they believe it has the potential to reshape the landscape of traditional organic electronics.

Their approach is based on generating a current in the ambipolar OFETs by illuminating the devices with light. The concentration of free carriers in the device generated due to this photoexcitation, modulate the current flow across the channel in the transistor, transforming it into to an electro-optical switch.