Metal–Insulator–Graphene diodes enable terahertz rectennas on flexible substrates

Researchers from AMO GmbH, RWTH Aachen University, Chalmers University and the University of Wuppertal have recently developed a novel type of graphene-based flexible energy harvester, which reportedly shows good prospects for powering wearable and conformal devices.

The device is a ‘rectenna’ – an antenna directly coupled to a diode, which is able to detect radiation and to transform it into a DC output. Rectennas working in the microwave region have been well established since the sixties, thanks to the availability of Schottky diodes with a sufficiently short response time. The challenge is to extend the working principle of rectennas to higher frequency ranges – in particular terahertz (THz) and optical frequencies.