A laser light source control system for continuous variable quantum key distribution
Siqing Zhang, H. Liang · Journal of Instrumentation · 2020
Compared with discrete variable quantum key distribution, continuous variable quantum key distribution (CVQKD) has the advantages of low cost, good stability, and high channel capacity, in addition to unconditional security and detectability for wiretapping. The basis of CVQKD system operation is the realization of loading information into photon quantum states. In this paper, a laser light source control system has realized the control and adjustment of the photon quantum states and completed the encoding of quantum states. In order to generate synchronous optical signals, FPGA, multi-channel DAC and micro power ADC are used to control the source of the synchronous optical laser. The control and modulation of multiple optical components are realized based on FPGA, multiple 16-bit 1.0 GSPS DACs and high-performance operational amplifiers. The electronic test results show that the system implements the control and adjustment functions of lasers, amplitude modulator, phase modulators, variable optical attenuators, polarization controllers, as well as detection of synchronized light. The performance of the laser light source control system fully meets the requirements of the CVQKD system.