根据差分相移量子密钥分发实验对高速电光调制电路的需求,利用固体开关技术和变压器隔离技术,设计出了重复频率为45 kHz、输出脉冲电压达到2 kV的电光调制电路,该电光调制电路由两部分组成,正负1 kV高压脉冲产生电路,其中正1 kV高压脉冲的上升沿为50.44 ns,下降沿为44.6 ns,负1 kV高压脉冲下降沿为52.29 ns,上升沿为50.44 ns.普克尔盒调制电路与光路进行联调,光路的消光比达到23 dB,完全满足了消光比为20 dB的实验需求.

According to the DPS-QKD (differential phase shift quantum key distribution) experiment demand for high-speed electro-optic modulator,the solid state switching technology and transformer isolation technology were applied to the design of a high speed electro optic modulator with a repetition rate of 45 kHz and a pulse of 2 kV.The modulation circuit includes two parts which can generate negative and positive 1000 V high voltage pulses respectively.The rise time and fall time of the positive high voltage pulse are 50.44 ns and 44.6 ns,and those of the negative high voltage pulses are 52.29 ns and 50.44 ns.The extinction ration is up to 23 dB when the modulator modulates the Pockels cell,which completely satisfies the need of DPS-QKD experiment.