准晶体中的高温原子扩散和特异热.
Yuki Nagai1,2,3, Yutaka Iwasaki4,5, Koichi Kitahara6
1Information Technology Center, The University of Tokyo, 6-2-3 Kashiwanoha, Kashiwa, Chiba 277-0882, Japan.
Physical review letters
|May 28, 2024
概括
准晶体由于相位活动而表现出异常的热容量. 在Al-Pd-Ru准晶体内原子的超原子波动解释了这种高温异常.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
背景情况:
- 准晶体具有有序的非周期性结构,具有独特的物理性质.
- 准晶体中的异常高温热容量表明隐藏的高维度.
- 与准晶体中的原子重新排列相关的Phason是这种异常的原因之一.
研究的目的:
- 研究准晶体中异常热容量的起源.
- 在现实材料中将理论阶段模型与实验观测联系起来.
- 探索准晶体高温行为背后的原子机制.
主要方法:
- 关于Al-Pd-Ru准晶体及其近似的实验研究.
- 分子模拟以模拟高温下的原子行为.
- 对原子扩散路径和重排的分析.
主要成果:
- 在高温下观察到原子扩散的不连续性跳跃.
- 链接扩散路径与超原子波动相关的相位重排.
- 为热容量异常提供了一种机械解释.
结论:
- 准晶体中的高温热容异常源于超原子波动.
- 这些波动与扩散的Nambu-Goldstone阶段模式有关.
- 这项研究弥合了准晶体特性理论和实验之间的差距.
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