光调制格式转换是全光通信中的一个关键技术。基于硅基微环谐振器的交叉相位调制(XPM)效应，可实现非归零(NRZ) 信号到归零(RZ) 信号的光调制格式转换。将探测光NRZ信号与抽运光时钟脉冲序列同步通过硅基微环谐振器，由于硅波导的XPM效应，抽运光上升沿与下降沿的功率改变使得探测光NRZ信号产生光频率的负啁啾与正啁啾，通过适当的光带通滤波器(OBPF)就可获得需要的RZ信号。研究了转换后RZ信号的质量与抽运光功率、脉宽以及OBPF对探测光的波长失谐量之间的关系。研究结果表明，利用硅基微环谐振器的XPM效应可实现芯片级的光调制格式转换。

The optical modulation format conversion is a key technique in the future all-optical communication. An optical modulation format conversion technique from non-return-to-zero (NRZ) signal to return-to-zero (RZ) signal is presented, based on the cross-phase modulation (XPM) effect in a silicon micro-ring resonator. When a NRZ signal acting as the probe and a periodic pulse train as the pump are launched into the silicon micro-ring resonator synchronously, the power change of the pump corresponding to the rising or falling edge leads to negative or positive chirp of the probe frequency caused by XPM. The converted RZ signal can be extracted by utilizing appropriate optical band pass filters (OBPFs). The dependence of the quality of converted RZ signal on the power and pulse-width of pump is studied, as well as that on the wavelength detuning of an OBPF to the probe. It is shown that the optical modulation format conversion can be achieved in a chip by the XPM nonlinear effect of the silicon micro-ring resonator.