The extinction spectra of colloidal solutions of gold nanoparticles produced by laser ablation in water and aqueous solutions of salts using two near-IR lasers with pulse durations of 200 ns and 1 ps are experimentally investigated. The extinction spectrum of the particles formed by ablation in aqueous solutions is characterised by enhanced optical density in the red and IR regions. This feature is due to the formation of elongated gold nanoparticles, as confirmed by transmission electron microscopy. The surface images of a gold target subjected to multipulse laser ablation exhibit micron and submicron structures.

中文翻译：

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水溶液中激光烧蚀产生的细长金纳米颗粒胶体溶液的光谱特征

实验研究了使用两个脉冲持续时间为200 ns和1 ps的近红外激光在水和盐水溶液中通过激光烧蚀制备的金纳米颗粒的胶体溶液的消光光谱。在水溶液中通过烧蚀形成的粒子的消光光谱的特征在于红色和IR区域的光密度提高。如透射电子显微镜所证实的，该特征归因于细长金纳米颗粒的形成。经受多脉冲激光烧蚀的金靶的表面图像显示出微米和亚微米结构。