Terahertz light controls atomically thin semiconductors

Physicists at Bielefeld University and the Leibniz Institute for Solid State and Materials Research Dresden (IFW Dresden) have developed a method to control atomically thin semiconductors using ultrashort light pulses.

The study published in Nature Communications could pave the way for components that are controlled at unprecedented speeds directly by light.

The researchers employ specially designed nanoscale antennas to convert terahertz light into vertical electric fields in atomically-thin semiconductors, such as MoS₂. These electric fields reach several megavolts per centimetre strength.

‘Traditionally, such vertical electric fields, used, for example, to switch transistors and other electronic devices, are applied using electronic gating, but this method is fundamentally limited to relatively slow response times,’ explains the project leader, physics professor Dmitry Turchinovich from Bielefeld University. ‘Our approach uses the terahertz light itself to generate the control signal within the semiconductor material – allowing an industry-compatible, light-driven, ultrafast optoelectronic technology that was not possible until now.’