Researchers unveil incredibly powerful, incredibly small laser

24 Jan 2018

Image: helfei/Shutterstock

Lasers are an essential part of modern technology, from smartphones to satellites. Now, the technology just took a major leap forward.

Photonics researchers are aiming to shrink more and more powerful beams in to the smallest lasers possible, and now an international team has produced the first high-powered, randomly polarised laser beam with a ‘Q switch’ laser, which typically emits pulses of light so brief that they’re measured in nanoseconds.

Q switch lasers have been a popular choice of photonics for decades now, and are already used in a variety of applications such as surgical procedures.

This is because they are highly precise resulting in less damage than when using traditional tools or instruments.

The technique behind this type of laser is called ‘Q switching’ and produces short but high-powered pulse outputs.

Similar to other lasers, Q switching uses an electric current to excite electrons in a laser medium, such as a crystal, emitting amplified light that can be polarised in one direction or another.

However, it is nearly impossible to change the randomly polarised light in a small Q laser.

10-times more powerful

To overcome this, the research team including Taichi Goto, assistant professor in the department of electrical and electronic information engineering at the Toyohashi University of Technology in Japan, used Q switching with a neodymium-yttrium-aluminium crystal to better control how the light moves within the laser cavity.

By creating short pulses, the researchers could change the polarisation of the laser resulting in the ability to switch pulses. Thus, the powerful Q laser was born.

The laser itself is one-tenth the size of a US one-cent coin and can produce beams 10-times more powerful than anything achieved with a larger laser.

“The experimental evidence provided in this study advances this research field toward the realisation of actively controllable integrated micro-lasers,” said Goto, who is second author of the paper.

Among some of the other breakthroughs in this area in recent months include a laser with the brightness of 1bn suns and so powerful that it changes how light and matter interact, with major implications.

Goto’s team’s research has been published in Scientific Reports.

Colm Gorey was a senior journalist with Silicon Republic