The new laser diode that emits the shortest-wavelength UV light, Now the research team is able to design a laser diode that emits deep ultraviolet light.

Our laser diode emits the shortest wavelength with a wavelength of 271.8 nanometers (nm) when a pulsing [electric] current is introduced at room temperature. Previous efforts to develop UV laser diodes only produce emissions of up to 336 nm, Sasaoka explained.

Diode lasers, which emit short-wave ultraviolet light as UV-C and range in wavelengths from 200 to 280 nm, can be used to disinfect health conditions and to treat skin diseases such as psoriasis and psoriasis for gas and DNA analysis. and the laser diode that emits the shortest-wavelength UV light.

UV laser diodes in Nagoya University solve several problems faced by scientists when developing this semiconductor device. The team used high quality aluminum nitride (AlN) substrates as the basis for the construction of the laser diode layer.

This is necessary because the lower quality of AlN contains a large number of defects which ultimately disrupt the efficiency of the laser diode’s active layer when converting electrical energy into light energy.

In a laser diode the ‘p-type’ and ‘n-type’ layers are separated by a ‘quantum well’. When an electric current is passed through a laser diode, positively charged openings in the p-type layer and negatively charged electrons in the n-type flow flow to the center to connect, energy in the form of light particles called photons, is released.

The researchers designed quantum so well that it emitted deep UV light. P and N type layers consist of aluminum gallium nitride (AlGaN). The cladding layer, also made of AlGaN, is arranged on both sides of the p and n layers. The layer below the n-type layer contains silicon impurities, a process called doping. Doping is used as a technique to change material properties.

The layer above the p-type layer is subject to distributed polarization doping which touches the layer without adding impurity.

The aluminum content of the p-side layer is designed so that it is highest at the bottom and reduced at the top. The researchers believe that this aluminum gradient increases the flow of positively charged openings. Finally, a top contact layer was added, which consisted of p-type AlGaN magnesium alloy.

Researchers have found that doping polarization of the layers by layer means that a “very low operating voltage” of 13.8 V is required to emit the “shortest wavelength” that has been reported by the research team so far and is now working with the Asahi Kasei Corporation together- together to achieve continuous UV radiation in room temperature and to develop UV-C semiconductor laser products.