Laser diode breakthrough for deep-ultraviolet light

This is the claim of scientists at Nagoya University, Japan who worked with the Asahi Kasei Corporation on the record-breaking laser diode. The research is published in Applied Physics Express.

In a statement, Prof Chiaki Sasaoka of Nagoya University's Centre for Integrated Research of Future Electronics said, "Our laser diode emits the world's shortest lasing wavelength, at 271.8nm, under pulsed [electric] current injection at room temperature.”

Solid start for laser research

Previous efforts in the development of ultraviolet laser diodes had only managed to achieve emissions down to 336 nm, Sasaoka said.

Laser diodes that emit short-wavelength ultraviolet light (UV-C) and is in the wavelength region of 200 to 280 nm, could be used for treating skin conditions such as psoriasis, or gas and DNA analysis.

The Nagoya University deep-ultraviolet laser diode is claimed to overcome several issues encountered by scientists working on these semiconducting devices.

The team used a high-quality aluminium nitride (AlN) substrate as their base for building up the layers of the laser diode. They say this is necessary, since lower quality AlN contains numerous defects that impact the efficiency of a laser diode's active layer in converting electrical into light energy.