The nonlinear optical materials with small footprint, low operating energy, ultrafast and large nonlinear optical response are highly required for the signal processing. Here, we investigated the broadband optical nonlinear response of the triangular gold nanoplates on indium tin oxide (ITO) coated glass, and obtained a large optical nonlinear enhancement at its localized surface plasmon resonance (LSPR) region at the wavelength of 780 nm, far from the ENZ (epsilon-near-zero) region of ITO. The measured nonlinear refractive index and nonlinear absorption coefficient can reach up to 8.39×10 ^-15 m ² /W and 5.81×10 ^-8 m/W, respectively. The experimental results highlight the noble metals’ potential for nonlinear optics and nanophotonics.

中文翻译：

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在氧化铟锡上增强三角形金纳米片中的光学非线性

信号处理需要具有小尺寸、低工作能量、超快和大非线性光学响应的​​非线性光学材料。在这里，我们研究了三角形金纳米片在氧化铟锡 (ITO) 涂层玻璃上的宽带光学非线性响应，并在波长为 780 nm 的局域表面等离子体共振 (LSPR) 区域获得了较大的光学非线性增强，远离ITO 的 ENZ（epsilon-near-zero）区域。测得的非线性折射率和非线性吸收系数分别可达8.39×10 ^-15 m ² /W和5.81×10 ^-8 m/W。实验结果突出了贵金属在非线性光学和纳米光子学方面的潜力。