The dual-wavelength-driven shrinkage of metal microstructures and hydrogel actuation are demonstrated by the fabrication of multi-metal microstructures in hydrogels by multiphoton photoreduction. Silver and gold microstructures were fabricated in a poly-N-isopropylacrylamide (PNIPAm) hydrogel. Because of the different optical resonances of the metals, wavelength-dependent shrinkage of metal microstructures was demonstrated concurrently with the volume change of the supporting hydrogel by light stimulation. Furthermore, the direction of actuation of the hydrogel was controlled by switching the wavelength of light stimulation. The results indicate the potential of multiphoton photoreduction for applications in light-driven optical components and micro-robots fabricated with soft materials.

中文翻译：

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多光子光还原技术用于水凝胶中双波长光驱动的收缩和驱动

通过多光子光还原在水凝胶中制造多金属微结构，证明了金属微结构和水凝胶致动的双波长驱动收缩。银和金的微结构是在聚N-异丙基丙烯酰胺（PNIPAm）水凝胶中制成的。由于金属的不同光学共振，因此证明了金属微结构的波长依赖性收缩与通过光刺激的支持水凝胶的体积变化同时发生。此外，通过切换光刺激的波长来控制水凝胶的致动方向。结果表明，多光子光还原技术可用于光驱动光学组件和用软材料制造的微型机器人中。