A new type of semiconductor laser has been created using the unique electronic properties of graphene. Designed in the UK by researchers at the University of Manchester, the prototype operates in the terahertz band and can be easily tuned to output radiation at specific wavelengths. The team says that its research could lead to the development of compact devices for a variety of different applications, from security scanning to medical imaging.
Terahertz radiation falls between the infrared and microwave regions of the electromagnetic spectrum and has the very useful property of passing through clothing, packaging and other common materials. As a result, terahertz radiation shows great promise in a wide range of applications, including security and medical scanning, drug and explosives detection as well as wireless communications. However, it has proven to be very difficult to create practical terahertz sources and detectors—so applications have so far been limited.