概括
五秒激光脉冲会在金和薄膜中引起微妙的变化. 这些激光诱导的修改,包括的化和再固化以及黄金的分层,导致光学反射率略有增加.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 激光物理 激光物理
背景情况:
- 研究薄膜中的激光物质相互作用对于理解材料修饰过程至关重要.
- 特别感兴趣的是在剥离前的制度,在这种情况下,细微的形态变化发生而不会造成大规模损伤.
研究的目的:
- 为了研究单一的femtosecond激光脉冲对纳米厚的黄金和薄膜在除值以下的影响.
- 为了将观察到的形态变化与现场光学反射性测量相关联.
主要方法:
- 用单一的400nm波长激光脉冲照明.
- 在现场监测光学反射率,使用弱探针束.
- 使用暗场,扫描电子和原子力显微镜以及电子反射散射衍射进行了表征.
- 使用分析,转移矩阵和两温度模型进行理论分析.
主要成果:
- 观察到微小,不可逆转的形态变化,包括中的亚波长分离和黄金中的分层.
- 测量到光学反射率的微小增加 (0.1-2%),与形态变化相吻合.
- 推断出层达到化温度,颗粒化并重新固化成更大的颗粒.
- 在中增加的反射性和裂变归因于谷物再固化;在黄金中归因于光学变化,归因于分层的标准效应.
结论:
- 激光诱导的化和再固化的粒在预剥离的制度导致增加的反射率和裂变.
- 黄金薄膜在预剥离状态下进行分层,会产生标准效应,从而增加光学反射率.
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