| 基于瞬态反射-透射技术的金属纳米薄膜电子和晶格传热动力学研究 |
| |
| 引用本文： | 吴文智,任世为,孔德贵,柴志军.基于瞬态反射-透射技术的金属纳米薄膜电子和晶格传热动力学研究[J].黑龙江大学工程学报,2021,12(4):41-50. |
| |
| 作者姓名： | 吴文智 任世为 孔德贵 柴志军 |
| |
| 作者单位： | 黑龙江大学 电子工程学院, 哈尔滨 150080 |
| |
| 摘 要： | 使用飞秒瞬态反射-透射技术研究了金和铜纳米薄膜的电子和晶格动力学,应用双温和Curde近似模型分析了金属薄膜的非平衡热传导动力学.假设在瞬态反射中电子-晶格耦合常数为常数的情况下,计算超快脉冲加热后的电子和晶格温度.金和铜纳米薄膜的反射和透射信号在初始2 ps内相似,随后时间里信号明显不同,透射模式下的电子-晶格耦合效应要比反射模式下的更强和更敏感.这是由于沿着膜厚方向的温度变化受到金属薄膜和基底间的界面散射影响造成的.在研究半透明薄膜的超快动力学过程中,需要同时考虑反射和透射情况.
|
| 关 键 词： | 双温模型 电子-声子耦合 超快脉冲加热 基底效应 Crude模型近似 |
A comparison of transient reflection and transmission techniques for electron and lattice dynamics in metal nanofilms |
| |
| Authors: | WU Wen-Zhi REN Shi-Wei KONG De-Gui CHAI Zhi-Jun |
| |
| Abstract: | The electron and lattice dynamics of gold and copper nanofilms are measured with femtosecond transient reflection and transmission techniques. Two-temperature model ( TTM) and Crude-model approximation are applied to study the mechanism of heat transfer for metal nanofilms theoretically. Electron and lattice temperatures are calculated by TTM, which assume electron-lattice coupling coefficient as a constant for gold and copper. Compared the results of reflection with transmission, the difference of electron relaxation is negligible at the first two picoseconds, but electron-lattice coupling effect in the transmission method is stronger and more sensitive than that of the reflection method under the identical experimental conditions. Change of temperature gradient along with the direction of film thickness and electron-lattice coupling resistance due to the boundary scattering are responsible for the difference between transient reflection and transmission data. Both transient reflection and transmission of semitransparent films should be considered together for the investigation on the mechanism of ultrafast dynamics. |
| |
| Keywords: | two-temperature model ( TTM ) electron-lattice coupling ultrafast pulsed laser heating substrate effect Crude-model approximation |
| 本文献已被 万方数据 等数据库收录！ |
