A nanoscale device to generate high-power terahertz waves

Terahertz (THz) waves fall between microwave and infrared radiation in the electromagnetic spectrum, oscillating at frequencies of between 100 billion and 30 trillion cycles per second. These waves are prized for their distinctive properties: they can penetrate paper, clothing, wood and walls, as well as detect air pollution. THz sources could revolutionize security and medical imaging systems. What's more, their ability to carry vast quantities of data could hold the key to faster wireless communications.