确定原子上的热迁移力
F Leroy1, A El Barraj1, F Cheynis1
1Aix Marseille Univ, CNRS, CINAM, AMUTECH, Marseille, France.
Physical review letters
|September 29, 2023
概括
超冷的岛在受到热梯度的影响时,会向更冷的地区迁移. 这项研究量化了推动纳米材料表面质量运输现象的原子力和运输热量.
科学领域:
- 材料科学 材料科学 材料科学
- 表面科学是一门学科.
- 纳米技术纳米技术
背景情况:
- 热梯度诱导纳米材料的表面质量传输.
- 量化原子流和理解潜在的机制是具有挑战性的.
研究的目的:
- 为了检查超冷 (Si) 岛屿在热梯度下的热迁移.
- 量化Si表面质量传输所涉及的原子力和传输热量.
主要方法:
- 使用低能电子显微镜 (LEEM) 在操作中进行检查.
- 将10^4 K/m的热梯度应用于Si(111)-1x1的适应性岛屿.
主要成果:
- 在0.26±0.06 nm/s的热梯度方向观察到岛屿迁移.
- 确定阿达托姆向寒冷地区移动.
- 量化了Si原子上的有效力为1.4±0.4×10^-8 eV/nm和传输热量Q*为1.2±0.4 eV.
结论:
- 运输的热量归因于步骤边缘的 adatom 创建和露台上的扩散.
- 提供了对纳米材料热迁移的原子机制的定量见解.
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