Researchers Harness Another Remarkable Property of Graphene

Another unique property of graphene has been harnessed by the University of Notre Dame researchers to control the terahertz band.

Graphene is a strong material that is made of a sheet of carbon atoms and includes a range of amazing properties. It is an excellent thermal insulator and is now used to modulate terahertz radiation in a better way.

Terahertz radiation provides exciting opportunities in chemical detection, medical imaging and communications. It is really difficult to produce, identify and modulate terahertz waves. It is noted that modulation or changing the height of the waves is essential as a modulated signal will be able to carry information and is highly flexible for biological and chemical sensing applications.

Among terahertz technologies that are currently available, few are based on tiny semiconductor transistor-like devices that have an ability to modulate a terahertz wave at room temperature. This is a key benefit offered by graphene when compared to earlier modulators, which could operate only at very cold temperatures. However, these transistor-like structures depend on a thin metal layer known as ‘metal gate’ to adjust the terahertz signal. The layer considerably decreases the signal strength and restricts the amount of signal that can be modulated. Researchers have replaced the metal gate with a single graphene layer and have estimated that the modulation range can be highly extended to more than 90%.