The latest research news of space communication laser
Satellite Internet system, with its global coverage, low latency and high bandwidth, has become the key direction of future communication technology development. Space laser communication is the core technology in the development of satellite communication system. Semiconductor laser shows wide application potential in space laser communication system by virtue of its high efficiency, long life, small size, light weight and excellent modulation characteristics. However, solar cosmic rays, galactic cosmic rays and a large number of high-energy charged particles such as protons, electrons and heavy ions in the geomagnetic capture belt in the space environment may lead to degradation of device performance and even lead to device failure, which seriously threatens the reliability and stability of space laser communication systems.
FIG1. Experimental device for laser performance evaluation
Recently, a research team in China has made important progress in the performance research of quantum dot lasers in the communication band for space. Through innovative band design and active region structure optimization, the team successfully developed the latest research results of space communication lasers, which have excellent performance in the high-energy particle environment, quantum dot lasers. They conducted an in-depth comparative analysis of the performance of different material systems in the space environment. The experimental results show that the quantum dot structure exhibits remarkable structural stability advantages in the high-energy particle environment of low Earth orbit.
Based on this discovery, the research team successfully designed and fabricated a new type of quantum dot laser. The device shows excellent performance in extreme environments: at 3MeV proton injection up to 7×1013 cm-2, the laser maintains a linewidth enhancement factor close to zero; The mean relative intensity noise (RIN) of the device is as low as -163 dB/Hz, even at the maximum injection volume, the RIN increases by only 1 dB/Hz. In addition, the laser can still work stably under the strong light feedback condition of -3.1dB. This achievement not only validates the latest research results of space communication lasers, but also provides a reliable light source solution for the construction of high-performance satellite communication networks.
Post time: Apr-01-2025