Laser-induced forward transferred silver nanomembrane with controllable light absorption

Abstract

Laser processing provides highly-controlled modification and on-demand fabrication of plasmon metal nanostructures for light absorption and photothermal convention. We present the laser-induced forward tansfer (LIFT) fabrication of silver nanomembranes in control of light absorption. By varying the hatch distance, different morphologies of randomly distributed plasmon silver nanostructures were produced, leading to well-controlled light absorption levels from 11% to 81% over broadband. The anti-reflection features were maintained below 17%. Equilibrated and plain absorptions were obtained throughout all absorption levels with a maximum intensity fluctuation of ±8.5% for the 225 µJ cases. The 45 µJ pulse energy can offer a highly equilibrated absorption at a 60% absorption level with an intensity fluctuation of ±1%. Pattern transfer was also achieved on a thin tape surface. The laser-transferred characters and patterns demonstrate a localized temperature rise. A rapid temperature rising of roughly 15 °C can be achieved within 1 s. The LIFT process is highly efficiently fabricated with a typical speed value of 10³ to 10⁵ cm²/h. The results indicated that LIFT is a well-controlled and efficient method for the production of optical films with specific absorption levels.

摘要

激光加工技术具有可控性强、按需制备的优点，可用于制备表面等离激元金属纳米结构，在光 吸收及光热转换领域具有广泛的应用价值。本文中采用激光诱导向前转移技术制备的银纳米薄膜，具 有光学吸收率可调的特性，兼容玻璃、柔性聚合物等衬底。通过控制激光线扫描间隔得到具有不同形 貌且随机分布的银纳米结构薄膜，其具有宽光谱平坦吸收特性，光吸收率可在11%到81%之间线性调 节，同时反射率低于17%。此外，利用优化的激光脉冲能量(45 μJ)得到了具有高平坦光吸收特性的银 纳米薄膜，其吸收率为60%，波动为±1%。这一技术可实现银纳米薄膜的图案化高速转移，转移速率 可达103到105 cm2/h。实验同时展示了银纳米结构薄膜的光热转换造成的图案化温升现象。