Spider silk is a tough, elastic and lightweight biomaterial, although there is a lack of tools available for non-invasive processing of silk structures. Here we show that nonlinear multiphoton interactions of silk with few-cycle femtosecond pulses allow the processing and heterostructuring of the material in ambient air. Two qualitatively different responses, bulging by multiphoton absorption and plasma-assisted ablation, are observed for low- and high-peak intensities, respectively. Plasma ablation allows us to make localized nanocuts, microrods, nanotips and periodic patterns with minimal damage while preserving molecular structure. The bulging regime facilitates confined bending and microwelding of silk with materials such as metal, glass and Kevlar with strengths comparable to pristine silk. Moreover, analysis of Raman bands of microwelded joints reveals that the polypeptide backbone remains intact while perturbing its weak hydrogen bonds. Using this approach, we fabricate silk-based functional topological microstructures, such as Mobiüs strips, chiral helices and silk-based sensors.

中文翻译：

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轻质丝绸的加工和异质结构

蜘蛛丝是一种坚韧，有弹性且重量轻的生物材料，尽管缺乏可用于非侵入性加工丝绸结构的工具。在这里，我们证明了丝绸与几个周期的飞秒脉冲的非线性多光子相互作用，使材料在环境空气中的处理和异质结构化成为可能。在低峰强度和高峰强度下，分别观察到两种性质上不同的响应，即多光子吸收引起的鼓胀和等离子体辅助的消融。等离子体消融使我们能够在保持分子结构的同时，以最小的损害制作出局部的纳米切口，微棒，纳米尖端和周期性图案。鼓胀状态有利于丝绸与金属，玻璃和凯夫拉尔纤维等材料的局限弯曲和微焊接，其强度可与原始丝绸媲美。而且，微焊接接头的拉曼带分析表明，多肽骨架保持完整，同时扰动了其弱氢键。使用这种方法，我们可以制造基于丝绸的功能拓扑微结构，例如Mobiüs条纹，手性螺旋和基于丝绸的传感器。