A project to study the near infrared semiconductor photoelectric materials at the nanometer level, undertaken by the Institute of Semiconductors, part of the Chinese Academy of Sciences, has achieved substantial progresses, under an initiative for advanced materials of the National 863 Program. The project has rolled out a GaInNAsSb/GaAs laser device with a work wavelength of 1.58 microns, capable of emitting consecutive laser beams under indoor temperatures. The development marks China?痵 possession of intellectual properties in developing GaAs based near infrared photoelectric materials and components.
Based on the 1.3-micron materials grown from molecular beams, researchers extended the optical wavelength of quantum wells to 1.55 microns, through increasing the amount of added nitrogen and using GaNAs layers. In the meantime, they noticeably raised the quality of crystals to the requirements for laser device making, using stibium as a surface activator for the growth with optimized anneal conditions. The new laser device realizes a consecutive 1.58-micron laser beam emission under indoor temperatures, with a threshold electric current density at 2.6 kiloampere/cm2, and an output larger than 30 miliwatts. The system gave out for the first time in the world a laser emission under indoor temperatures, using GaAs based semiconductor laser device above 1.5 micron. The development confirms the feasibility of the full applications of GaAs components at the wavelengths ranging from 1.2 to 1.6 microns, which heralds a bright perspective for commercial applications in optical communications.
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