[论文解读] Enhanced four-wave-mixing with 2D layered graphene oxide films integrated with CMOS compatible micro-ring resonators

Jiayang Wu, Yunyi Yang+9 more|arXiv (Cornell University)|Feb 11, 2020

Photonic and Optical Devices参考文献 76被引用 33

一句话总结

通过在 CMOS 兼容的微环谐振腔中集成分层的石墨烯氧化物薄层，展示增强的四波混频并实现显著的转换效率提升。

ABSTRACT

Layered 2D graphene oxide (GO) films are integrated with microring resonators (MRRs) to experimentally demonstrate enhanced nonlinear optics in the form of four wave mixing (FWM). Both uniformly coated and patterned GO films are integrated on CMOS compatible doped silica MRRs using a large area, transfer free, layer by layer GO coating method together with photolithography and lift off processes, yielding precise control of the film thickness, placement, and coating length. The high Kerr nonlinearity and low loss of the GO films combined with the strong light matter interaction within the MRRs results in a significant improvement in the FWM efficiency in the hybrid MRRs. Detailed FWM measurements are performed at different pump powers and resonant wavelengths for the uniformly coated MRRs with 1 to 5 layers of GO as well as the patterned devices with 10 to 50 layers of GO. The experimental results show good agreement with theory, achieving up to 7.6 dB enhancement in the FWM conversion efficiency (CE) for an MRR uniformly coated with 1 layer of GO and 10.3 dB for a patterned device with 50 layers of GO. By fitting the measured CE as a function of pump power for devices with different numbers of GO layers, we also extract the dependence of the third-order nonlinearity on layer number and pump power, revealing interesting physical insights about the evolution of the layered GO films from 2D monolayers to quasi bulk like behavior. These results confirm the high nonlinear optical performance of integrated photonic resonators incorporated with 2D layered GO films.

研究动机与目标

• 探索将分层石墨烯氧化物薄层与 CMOS 兼容的微环谐振腔集成，以提升非线性光学性能。
• 量化 GO 层数和图案化对四波混频转换效率的影响。
• 建立一种无需转移的涂层方法，以在掺杂二氧化硅 MRR 上实现 GO 薄膜的受控厚度和定位。

提出的方法

• 使用大面积、无需转移的逐层 GO 涂覆方法，结合光刻和升离工艺，在掺杂二氧化硅 MRR 上沉积 GO。
• 制备均匀涂覆的 MRR（1–5 层 GO）和带有图案的 GO 器件（10–50 层 GO）。
• 在不同泵浦功率和谐振波长下进行四波混频测量，以提取转换效率。
• 拟合 CE 相对于泵浦功率的关系，以研究三阶非线性随 GO 层数和泵浦功率的依赖性。
• 将实验结果与理论模型进行比较，以解释非线性增强。
• 报告观察到的 CE 增强，并将其与 GO 层从二维单层到准体行为的演变联系起来。

实验结果

研究问题

• RQ1 将 GO 薄层与 CMOS 兼容的 MRR 融合会如何影响 FWM 效率？
• RQ2 FWM 转换效率对 GO 层数和薄膜图案化的依赖性是多少？
• RQ3 从单层到准体的 GO 层演变如何影响混合体系中的三阶非线性？

主要发现

• 1 层均匀 GO 涂覆在 FWM 转换效率上实现高达 7.6 dB 的提升。
• 带有 50 层 GO 的图案化器件在 FWM 转换效率上可实现高达 10.3 dB 的提升。
• CE 对泵浦功率的依赖数据可用于提取三阶非线性随层数和泵浦功率的关系。
• 结果与理论一致，支持与二维层状 GO 薄膜集成的 MRRs 的高非线性光学性能。
• 展示了一种可规模化、与 CMOS 兼容的基于 GO 的增强型非线性光子学方法。