Bekele Dagmawi A, Yu Yi, Hu Hao, Guan Pengyu, Galili Michael, Ottaviano Luisa, Oxenløwe Leif Katsuo, Yvind Kresten, Mork Jesper
Opt Express. 2018 Jul 23;26(15):19596-19605. doi: 10.1364/OE.26.019596.
We experimentally demonstrate the use of photonic crystal Fano resonances for reshaping optical data signals. We show that the combination of an asymmetric Fano resonance and carrier-induced nonlinear effects in a nanocavity can be used to realize a nonlinear power transfer function, which is a key functionality for optical signal regeneration, particularly for suppression of amplitude fluctuations of data signals. The experimental results are explained using simulations based on coupled-mode theory and also compared to the case of using conventional Lorentzian-shaped resonances. Using indium phosphide photonic crystal membrane structures, we demonstrate reshaping of 2 Gbit/s and 10 Gbit/s return-to-zero on-off keying (RZ-OOK) data signals at telecom wavelengths around 1550 nm. Eye diagrams of the reshaped signals show that amplitude noise fluctuations can be significantly suppressed. The reshaped signals are quantitatively analyzed using bit-error ratio (BER) measurements, which show up to 2 dB receiver sensitivity improvement at a BER of 10 compared to a degraded input noisy signal. Due to efficient light-matter interaction in the high-quality factor and small mode-volume photonic crystal nanocavity, low energy consumption, down to 104 fJ/bit and 41 fJ/bit for 2 Gbit/s and 10 Gbit/s, respectively, has been achieved. Device perspectives and limitations are discussed.
我们通过实验证明了利用光子晶体法诺共振来重塑光数据信号。我们表明，纳米腔中不对称法诺共振与载流子诱导非线性效应的结合可用于实现非线性功率传递函数，这是光信号再生的关键功能，特别是用于抑制数据信号的幅度波动。利用基于耦合模理论的模拟对实验结果进行了解释，并与使用传统洛伦兹形共振的情况进行了比较。使用磷化铟光子晶体膜结构，我们展示了在1550nm左右的电信波长下对2 Gbit/s和10 Gbit/s归零开关键控（RZ-OOK）数据信号的重塑。重塑信号的眼图表明，幅度噪声波动可得到显著抑制。使用误码率（BER）测量对重塑信号进行了定量分析，结果表明，与退化的输入噪声信号相比，在误码率为10时，接收器灵敏度提高了2 dB。由于在高品质因数和小模式体积的光子晶体纳米腔中存在高效的光-物质相互作用，分别实现了2 Gbit/s和10 Gbit/s低至104 fJ/bit和41 fJ/bit的低能耗。讨论了器件的前景和局限性。
