For 64-Gbaud operation and beyond, we developed a power efficient high-bandwidth coherent driver modulator composed of a linear four-channel ultra-low power CMOS driver IC and an InP-based dual-polarization IQ modulator. The CMOS driver was fabricated in 65-nm CMOS technology and showed power dissipation of <1 W owing to the use of an open-drain configuration and a stacked current-mode architecture. Moreover, by optimizing the temperature of the thermoelectric cooler that controls the modulator operating temperature, the coherent driver modulator achieved consumed power of <2.5 W at case temperatures of −5 to 75 °C and <2.8 W under −5 to 85 °C. As far as we know, this is the lowest power dissipation for a coherent driver modulator with an InP modulator chip. In addition, by employing a circuit that suppresses temperature dependence of RF characteristics in the CMOS driver, we achieved the 3-dB electro-optical bandwidth of >44 GHz and the variation of 2.0 GHz under the 25° to 85 °C condition. Furthermore, we obtained good back-to-back bit-error-rate performance in up to dual polarization 80-Gbaud 16-QAM modulation.

中文翻译：

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500-Gb/s/λ 基于 InP 的超低功耗和低温依赖性高带宽相干驱动调制器的运行

对于 64 Gbaud 及更高的操作，我们开发了一种高能效高带宽相干驱动器调制器，由一个线性四通道超低功耗 CMOS 驱动器 IC 和一个基于 InP 的双极化 IQ 调制器组成。CMOS 驱动器采用 65 纳米 CMOS 技术制造，由于使用开漏配置和堆叠电流模式架构，其功耗小于 1 W。此外，通过优化控制调制器工作温度的热电冷却器的温度，相干驱动器调制器在 -5 至 75 °C 的外壳温度下实现了 <2.5 W 的消耗功率，在 -5 到 85 °C 下实现了 <2.8 W 的消耗功率。据我们所知，这是具有 InP 调制器芯片的相干驱动器调制器的最低功耗。此外，通过采用抑制 CMOS 驱动器中 RF 特性的温度依赖性的电路，我们实现了 >44 GHz 的 3-dB 电光带宽和 25° 至 85°C 条件下的 2.0 GHz 变化。此外，我们在高达双极化 80-Gbaud 16-QAM 调制中获得了良好的背靠背误码率性能。