Different types of lasers are built on silicon materials

Building a quantum cascade laser on silicon is extremely challenging, mainly due to the strong absorption of SiO2 in the long-wavelength mid-infrared band. “This means that we not only need to build different types of laser pointer on silicon materials, but also different types of silicon waveguides.” The project leader said: “We built SONOI waveguides and used silicon nitride under the silicon waveguides. Layer instead of just SiO2.”

This achievement will be widely used in spectrochemistry, gas detection, astronomy, ocean exploration, thermal imaging, explosives detection and free space communications. New compact eye-safe lasers. Scientists from the research teams of Moscow State University and Belarusian State Technical University have developed a new type of laser. It is a compact laser source whose wavelength is harmless to human eyes. The laser can be used in medical, communication and scientific research fields.

650nm 10mW Red Light Laser Pointer Pocket

The laser beam in the wavelength range of 1500 to 1600 nm is harmless to human eyes and has practical applications in medical, ranging, communication and other fields. The cornea and lens of the human eye have a high absorption coefficient for these spectra, so only a small part of the energy reaches the sensitive area of ​​the retina. And the 1500 to 1600nm wavelength range spectrum has low loss characteristics in the air, so it can be applied to the communications industry.

So far, the light source in this band is mainly erbium-doped and ytterbium-doped phosphate crystal solid-state green laser pointer. This laser has a simple and compact structure, and can generate short pulses by Q-switching. At the same time, the low thermal conductivity structure of the erbium phosphate crystal limits the application range of this continuous diode system. To avoid this problem, crystal structures containing erbium and ytterbium will come in handy.

Black scale-based fiber mode-locked lasers. The Shenzhen Peacock innovation team led by Professor Zhang Han from Shenzhen University-National University of Singapore Optoelectronics Collaborative Innovation Center developed a black phosphor-based fiber mode-locked laser for the first time, and obtained the output signal of an ultrashort pulse laser. .