Wavelength conversion technique for optical frequency dissemination applications

We demonstrate coherent wavelength conversion capable to cover the entire C-band by modulating the incoming optical carrier with a compact Fabry-Perot cavity embedded phase modulator and by optical injection locking (OIL) a semiconductor laser to a tone of the generated optical frequency comb. The phase noise of the converted optical carrier over 1 THz frequency interval is measured to be -40 dBc/Hz at 10 Hz offset and the frequency stability is better than 2 × 10-17 level for averaging times >1000 s, making this technique a promising solution for comparisons of state-of-the-art optical clocks over complex fiber networks.

本研究展示了一种可覆盖全C波段（C-band）的相干波长转换方案：通过集成紧凑法布里-珀罗腔（Fabry-Perot cavity）的相位调制器对入射光载波进行调制，并采用光注入锁定（optical injection locking, OIL）技术将半导体激光器锁定至所生成光频梳（optical frequency comb）的某一梳齿频率上。经测试，在1 THz的频率区间内，转换后光载波的相位噪声在10 Hz频偏处测得为-40 dBc/Hz；当平均时间超过1000秒时，其频率稳定性优于2×10^-17量级。该技术有望成为在复杂光纤网络中开展当前最先进光钟比对的极具潜力的解决方案。