QuantumCTek Co., Ltd., together with its subsidiaries, engages in the research, development, production, and sale of quantum communication, computing, and precision measurement products in China. The company offers quantum-secure communication network core equipment comprising miniaturized quantum key distribution terminals, and polarization coding quantum key distribution and management terminals; high speed and miniaturized time-bin phase-coding quantum key distribution terminals; portable ground stations for satellite QKD; quantum key management, key system exchange cipher, and optical switching machines, as well as wavelength division multiplexing terminals of quantum channels and classical channels; and fixed network encryption application products. It also provides mobile encryption application products; operating system software, such as Gou-Dun quantum-secure communication network management system, and Gou-Dun network operation and maintenance system; and quantum computer products. In addition, the company offers optoelectronic products comprising single-photon detectors; light sources; and random number sources, which include multi-function high speed ps-pulse laser sources, periodically poled lithium niobate waveguides, geiger-mode InGaAs avalanche photodiodes, micro-processor compensated variable optical attenuators, QFPS fiber phase shifters, manual polarization controllers, and dynamic polarization controllers, as well as teaching systems and scientific instruments; and single photon imaging, cold atomic gravimeters, and femtosecond laser frequency combs.