隐藏领域边界动态朝着晶体完美的方向发展
Anudeep Mangu1,2, Vladimir A Stoica3,4, Hao Zheng4,5
1Department of Materials Science and Engineering, Stanford University, Stanford, CA 94305.
概括
我们使用超快X射线光谱学揭示了铁电超级网中的复杂,不可逆转的动态. 这项研究揭示了在光诱导相位过渡期间缺陷如何形成和消失,为无序系统提供了洞察力.
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
- 非线性动力学是一种非线性动力学.
背景情况:
- 了解异质性和混乱在不平衡物理中至关重要,影响眼镜和活性物质.
- 探测微观轨迹,波动和增长是分析不可逆转过程的关键.
- 模型系统可以阐明一般的不平衡现象,并为信息处理技术提供信息.
研究的目的:
- 在光引起的相位过渡过程中解决不平衡,异质和不可逆转的中等层次动力学.
- 为了研究核化,缺陷形成和铁电超级网格中的消灭.
- 了解这些复杂动态的时间尺度和机制.
主要方法:
- 超快单射X射线光子相关谱学 (XPCS) 的应用.
- 对可调节的 (PbTiO3) 16/(SrTiO3) 16铁电超网格进行研究.
- 分析中尺度动态,包括相位过渡核和缺陷演变.
主要成果:
- 捕捉了光诱导阶段的核化和短暂的中等尺度缺陷的形成/消灭.
- 确定了一个不平衡的相关反应,在时间尺度上跨越了10个数量级.
- 观察到多步放松行为和依赖时间的长时间相关性,由随机,非马科维亚域壁面动力学解释.
结论:
- 铁电超级网格作为研究可调节相位过渡和拓动态的平台.
- 在异质不平衡系统中,XPCS可以解决复杂的动态,包括缺陷演变.
- 这些发现为探讨无序媒体中的相关动态提供了一个框架,并提供了对信息处理中的能量/速度限制的见解.
相关概念视频
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Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
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01:25Crystal Growth: Principles of Crystallization
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02:58Crystal Field Theory - Octahedral Complexes
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Crystal Field Theory
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02:22Structures of Solids
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02:18X-ray Crystallography
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The size of the unit cell and the arrangement of atoms in a crystal may be determined from measurements of the diffraction of X-rays by the crystal, termed X-ray crystallography.
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Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
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