On chip waveguide optical amplifiers have been extensively studied over the last years, with a wide variety of materials tested and proposed for different applications. Among the most prominent solutions for on-chip amplification, erbium doped waveguide amplifiers (EDWAs) are able to offer attractive performance metrics that can exceed SOA-based amplification solutions in traditional single and multi-channel systems. In this letter, we experimentally demonstrate a record high $8\times 40$ Gbps non return to zero (NRZ) wavelength division multiplexing (WDM) data amplification through a 5.9 cm long on-chip amplifier consisting of an erbium-doped aluminum oxide spiral waveguide monolithically integrated on the Si ₃ N ₄ platform. Experimental results show more than 12.7 dB amplification per channel for low saturation total input power of −2.75 dBm, and clear eye diagrams and bit-error rate values below the KR4-FEC limit of $2\times 10 ^{-5}$ for all eight channels without any digital signal processing (DSP) applied to the signal to the receiver or transmitter side. The high losses from the fiber to chip interfaces, however, prevented achieving device net gain.

中文翻译：

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单片集成 Al2O3:Er3+-Si3N4 波导放大器中的 8×40 Gbps WDM 放大

片上波导光放大器在过去几年中得到了广泛的研究，针对不同的应用测试和提出了多种材料。在最突出的片上放大解决方案中，掺铒波导放大器 (EDWA) 能够提供有吸引力的性能指标，其性能指标可能超过传统单通道和多通道系统中基于 SOA 的放大解决方案。在这封信中，我们通过实验证明了创纪录的高 $8\乘以 40$ Gbps 不归零 (NRZ) 波分复用 (WDM) 数据通过 5.9 厘米长的片上放大器进行放大，该放大器由单片集成在 Si ₃ N ₄平台上的掺铒氧化铝螺旋波导组成 。实验结果表明，对于 -2.75 dBm 的低饱和总输入功率，每通道具有超过 12.7 dB 的放大率，以及低于 KR4-FEC 限制的清晰眼图和误码率值 $2\times 10 ^{-5}$ 对于所有八个通道，没有对接收器或发射器端的信号应用任何数字信号处理 (DSP)。然而，光纤到芯片接口的高损耗阻碍了设备净增益的实现。