Recently, the Changchun Institute of Optics and Mechanics of the Chinese Academy of Sciences has made progress in the research and development of special chips for quantum gyroscopes, and developed a 795-nanometer vertical cavity surface emitting laser chip, which has practical application value. The related results were published in the journal Optics Express.
The team achieved single-mode operation of VCSELs with large oxidized apertures by solving the key issues of the mode stability of VCSELs and the mutual restriction of output power. The new device developed by the team has an output power of 4.1mW (milliwatts) at a temperature of 80°C, a side mode suppression ratio of 41.68dB (decibel), and an orthogonal polarization suppression ratio of 27.6dB.
The chip is used as the light source of quantum gyroscope, and the experimental test results are good, indicating that it has good practical application value. The research work was funded by the National Key Research and Development Program and the National Natural Science Foundation of China.
(a) P-I-V characteristic curves of VCSEL at different temperatures, the inset is the actual chip image;
(b) The near-field light spots of VCSELs at different currents at 80°C;
(c) Spectral properties of VCSELs; (d) Polarization properties of VCSELs;
(e) The signal-to-noise ratio test result of the quantum gyroscope using VCSEL as the pump source;
Changchun Institute of Optics and Mechanics has achieved many breakthroughs in research since its establishment.
In June 2020, the Sino-German Center of Changchun Institute of Optics and Mechanics carried out research on high-speed, low-power vertical cavity surface emitting lasers (VCSELs), in order to achieve high-speed, low-power data transmission.
The research team achieved 50Gbit/s high-speed data transmission and 240fJ/bit energy consumption based on PAM2 modulation in OM5 multimode fiber, and verified the 850nm, 880nm, 910nm, 940nm four-wavelength VCSELs based on wavelength division multiplexing at 200Gbit/s high-speed data transmission scheme.
On this basis, the research team further achieved ultra-low power consumption of 100fJ/bit based on 980nm VCSEL single-channel 25Gbit/s rate by optimizing the photon lifetime of the VCSEL cavity while reducing the VCSEL bias current. Under the condition of ensuring the transmission rate of 200 Gbit/s, the total energy consumption can be effectively reduced to 50% of the 4-channel 50Gbit/s scheme (Table 1).
Since the VCSEL operates at a lower bias current, this solution can not only prolong the life of the VCSEL chip, but also reduce the heat dissipation of the VCSEL, which can further reduce the energy consumption required for device cooling.
