Building the world’s most powerful terahertz laser chip
The University of Leeds says its researchers have taken the lead in the race to build the world’s most powerful terahertz laser chip.
A paper in the Institution of Engineering and Technology’s (IET) journal Electronics Letters reports that the Leeds team has exceeded a 1 Watt output power from a quantum cascade terahertz laser.
This, says the university, more than doubles landmarks set by the Massachusetts Institute of Technology (MIT) and subsequently by a team from Vienna last year.
In October 2013, Vienna University of Technology announced that its researchers had smashed the world record output power for quantum cascade terahertz lasers previously held by Massachusetts Institute of Technology (MIT). The Austrian team reported an output of 0.47 Watt from a single laser facet, nearly double the output power reported by the MIT team. The Leeds group has now achieved an output of more than 1 Watt from a single laser facet.
The quantum cascade terahertz lasers being developed by Leeds are only a few square millimetres in size.
This work was mainly funded by the Engineering and Physical Sciences Research Council (EPSRC).
“The process of making these lasers is extraordinarily delicate,” says Professor Edmund Linfield, Professor of Terahertz Electronics in the University’s School of Electronic and Electrical Engineering. “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 Leeds in fabricating these layered semiconductors, together with our ability to engineer these materials subsequently into suitable and powerful laser devices.”
“The University of Leeds has been an international leader in terahertz engineering for many years,” Professor Giles Davies, Professor of Electronic and Photonic Engineering in the School of Electronic and Electrical Engineering. “This work is a key step toward increasing the power of these lasers while keeping them compact and affordable enough to deliver the range of applications promised by terahertz technology.”