飞秒、纳米时/空尺度热输运机理研究

项目名称： 飞秒、纳米时/空尺度热输运机理研究

项目编号： No.51336009

项目类型： 重点项目

立项/批准年度： 2014

项目学科： 能源与动力工程

项目作者： 唐大伟

作者单位： 大连理工大学

项目金额： 300万元

中文摘要： 飞秒、纳米时/空尺度下热输运过程具有强烈的非平衡特征，是目前热物理界乃至物理界迫切需要解决的最前沿难题之一。本课题以实验为主导，理论分析与数值模拟为支撑，系统研究飞秒时间尺度下多载能粒子热输运机理和纳米空间尺度下材料内部、界面的热输运特性。主要工作包括：建立双波长飞秒激光抽运探测系统，大幅（3个数量级）提高测量精度，解决常规单波长系统中信噪比过低的难题；并结合近场光学系统，同时实现飞秒、纳米时/空分辨的动态热输运特性测量，揭示固-固界面热整流现象以及界面热阻受尺度、结构影响的规律；采用求解BTE的方法分别对多载能粒子系统的各亚系统进行模拟，引入并实验获得亚系统之间相互作用的弛豫时间，揭示多载能粒子系统热输运过程的物理本质。本课题可推进飞秒、纳米时/空尺度下热输运理论框架的完善，为解决高频高热流微电子器件热管理及超短脉冲激光微加工等过程中的热设计问题提供科学依据。

中文关键词： 飞秒；纳米时/空尺度;热输运;飞秒激光抽运探测;近场光学系统;界面

英文摘要： The heat transport process at the femtosecond-nanometer scale, having strong non-equilibrium characteristics, is one of the most leading edge problems urgent to solve at present in the fields of thermophysics and even physics. In this program, the heat transport mechanism of the multiple energetic carriers at the femtosecond temporal scale, and the heat transport properties of the material interior and interface at the nanometer spatial scale are to be systematically investigated, through experiment as a dominant method, and theoretical analysis and numerical simulation as supports. Major tasks include: setting up a dual-wavelength femtosecond laser pump-probe system, substantially increasing the measurement precision (by 3 orders of magnitude), solving the problem of too low signal to noise ratio in the conventional single-wavelength system; simultaneously realizing the dynamic measurement of the heat transport characteristics at the femtosecond -nanometer resolutions with the aid of near-field optics, revealing the thermal rectification phenomenon at the solid-solid interface and the influence of the spatial-scale and structure on the thermal resistance of the interface; simulating the respective subsystems of the multi-energetic-carrier system by the method of solving BET, introducing and acquiring the relaxation time of the interaction between individual subsystems by experiment, revealing the physical mechanism of the heat transport process of the multi-energetic-carrier system. This program is to promote the perfection of the frame of heat transport theory at the femtosecond-nanometer scale, to provide scientific basis for solving the thermal design problems in the thermal management of high-frequency high-heat-flux micro-electronic components and in the ultra-short pulse laser micromachining.

英文关键词： femtosecond/nanometer scale;heat transport ;femtosecond laser pump-probe ;near-field optical system;interface