Abstract The AlGaAs material platform has been intensively used to develop nonlinear photonic devices on-a-chip, thanks to its superior nonlinear optical properties. We propose a new AlGaAs waveguide geometry, called half-core etched, which represents a compromise between two previously studied geometries, namely the nanowire and strip-loaded waveguides, combining their best qualities. We performed tunable four-wave mixing (FWM) experiments in all three of these geometries in the telecommunications C-band (wavelengths around 1550 nm ), with a pulsed pump beam and a continuous-wave (CW) signal beam. The maximum FWM peak efficiencies achieved in the nanowire, strip-loaded and half-core geometries were about − 5 dB , − 8 dB and − 9 dB , respectively. These values are among the highest reported in AlGaAs waveguides. The signal-to-idler conversion ranges were also remarkable: 161 nm for the strip-loaded and half-core waveguides and 152 nm for the nanowire. Based on our findings, we conclude that the half-core geometry is an alternative approach to the nanowire geometry, which has been earlier deemed the most efficient geometry, to perform wavelength conversion in the spectral region above the half-bandgap. Moreover, we show that the half-core geometry exhibits fewer issues associated with multiphoton absorption than the nanowire geometry.

中文翻译：

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三种不同几何形状的 AlGaAs 波导中的可调四波混频

摘要 AlGaAs 材料平台由于其卓越的非线性光学特性，已被广泛用于开发片上非线性光子器件。我们提出了一种新的 AlGaAs 波导几何形状，称为半芯蚀刻，它代表了两种先前研究的几何形状之间的折衷，即纳米线和带状波导，结合了它们的最佳品质。我们在电信 C 波段（波长约 1550 nm）中对所有这三种几何结构进行了可调四波混频 (FWM) 实验，使用脉冲泵浦光束和连续波 (CW) 信号光束。在纳米线、带状加载和半芯几何结构中实现的最大 FWM 峰值效率分别约为 - 5 dB、- 8 dB 和 - 9 dB。这些值是 AlGaAs 波导中报告的最高值之​​一。信号到空闲的转换范围也很显着：带状加载和半芯波导为 161 nm，纳米线为 152 nm。根据我们的发现，我们得出结论，半芯几何结构是纳米线几何结构的替代方法，纳米线几何结构早先被认为是最有效的几何结构，可以在半带隙以上的光谱区域进行波长转换。此外，我们表明，与纳米线几何结构相比，半核几何结构与多光子吸收相关的问题更少。在半带隙以上的光谱区域进行波长转换。此外，我们表明，与纳米线几何结构相比，半核几何结构与多光子吸收相关的问题更少。在半带隙以上的光谱区域进行波长转换。此外，我们表明，与纳米线几何结构相比，半核几何结构与多光子吸收相关的问题更少。