An ultrafast microring modulator (MRM) is fabricated and presented with ${\mathit{V}}_{\pi }·\mathit{L}$ of $0.825\mathrm{V}·\mathrm{cm}$. A 240 Gb/s PAM-8 signal transmission over 2 km standard single-mode fiber (SSMF) is experimentally demonstrated. PN junction doping concentration is optimized, and the overall performance of the MRM is improved. Optical peaking is introduced to further extend the EO bandwidth from 52 to 110 GHz by detuning the input wavelength. A titanium nitride heater with 0.1 nm/mW tuning efficiency is implemented above the MRM to adjust the resonant wavelength. High bit rate modulations based on the high-performance and compact MRM are carried out. By adopting off-line signal processing in the transmitter and receiver side, 120 Gb/s NRZ, 220 Gb/s PAM-4, and 240 Gb/s PAM-8 are measured with the back-to-back bit error ratio (BER) of $5.5\times {10}^{-4}$, $1.5\times {10}^{-2}$, and $1.4\times {10}^{-2}$, respectively. A BER with different received optical power and 2 km SSMF transmission is also investigated. The BER for 220 Gb/s PAM-4 and 240 Gb/s PAM-8 after 2 km SSMF transmission is calculated to be $1.7\times {10}^{-2}$ and $1.5\times {10}^{-2}$, which meet with the threshold of soft-decision forward-error correction, respectively.

中文翻译：

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基于超快硅微环调制器的 240 Gb/s 光传输

制造并展示了一种超快微环调制器（MRM）${\mathit{五}}_{\pi }·\mathit{大号}$的$0.825\mathrm{五}·\mathrm{厘米}$. 通过 2 km 标准单模光纤 (SSMF) 传输 240 Gb/s PAM-8 信号进行了实验演示。优化了PN结掺杂浓度，提高了MRM的整体性能。引入光学峰值以通过失谐输入波长将 EO 带宽从 52 GHz 进一步扩展至 110 GHz。具有 0.1 nm/mW 调谐效率的氮化钛加热器在 MRM 上方实施，以调整谐振波长。执行基于高性能和紧凑型 MRM 的高比特率调制。通过在发送端和接收端采用离线信号处理，120 Gb/s NRZ、220 Gb/s PAM-4 和 240 Gb/s PAM-8 测量背靠背误码率） 的$5.5\times {10}^{-4}$,$1.5\times {10}^{-2}$， 和$1.4\times {10}^{-2}$， 分别。还研究了具有不同接收光功率和 2 km SSMF 传输的 BER。2 km SSMF 传输后 220 Gb/s PAM-4 和 240 Gb/s PAM-8 的 BER 计算为$1.7\times {10}^{-2}$和$1.5\times {10}^{-2}$，分别满足软判决前向纠错的阈值。