British researchers have built the world’s most powerful terahertz laser chip, an advance that may enable improved security scanning and medical imaging.
Researchers from the University of
The research was published in the
Terahertz waves, which lie in the part of the electromagnetic spectrum between infrared and microwaves, can penetrate materials that block visible light and have a wide range of possible uses including chemical analysis, security scanning, medical imaging, and telecommunications.
Potential applications included monitoring pharmaceutical products, the remote sensing of chemical signatures of explosives in unopened envelopes, and the non-invasive detection of cancers in the human body. However, one of the main challenges for scientists and engineers is making the lasers powerful and compact enough to be useful.
“Although it is possible to build large instruments that generate powerful beams of terahertz radiation, these instruments are only useful for a limited set of applications,” said
“We need terahertz lasers that not only offer high power, but are also portable and cost less,” Linfield said.
The quantum cascade terahertz lasers being developed by
Professor Linfield said: “The process of making these lasers is extraordinarily delicate. Layers of different semiconductors such as gallium arsenide are built up one atomic monolayer at a time. We control the thickness and composition of each individual layer very accurately and build up a semiconductor material of between typically 1,000 and 2,000 layers.
The record power of our new laser is due to the expertise that we have developed at
The Austrian team reported an output of 0.47 Watt from a single laser facet, nearly double the output power reported by the