Two objects of intense interest in the world of cutting-edge technology – graphene and terahertz radiation – seem to be well-suited for each other, even though no such close connection has been recognized until recently.
Terahertz radiation lies in the portion of the electromagnetic spectrum where the wave frequency is around a trillion cycles per second – sandwiched in between the microwave and infrared bands. It has received little attention until recent years, because it is difficult both to produce and to detect. That situation has been changing, and it may start to change even more rapidly.
It turns out that graphene – the new wonder-material consisting of single-layers of ordinary graphite – responds strongly to terahertz waves.
Graphene responds strongly to light at terahertz frequencies and this could be fine-tuned to make practical devices. That is the conclusion of researchers in the US who believe that their findings could help lead to graphene finding use in a wide range of applications that include medical imaging and security screening.
Terahertz radiation lies between the microwave and mid-infrared regions of the electromagnetic spectrum. It passes through clothing and packaging but is strongly absorbed by metals and other inorganic substances, making it of great interest to those developing airport security scanners. However, the radiation has proven extremely difficult to create, manipulate and detect.