Structural aspects of crystal nucleation in undercooled liquids are explored using a nonlinear hydrodynamic theory of crystallization proposed recently [G. I. Toth et al., J. Phys.: Condens. Matter 26, 055001 (2014)], which is based on combining fluctuating hydrodynamics with the phase-field crystal theory. We show that in this hydrodynamic approach not only homogeneous and heterogeneous nucleation processes are accessible, but also growth front nucleation, which leads to the formation of new (differently oriented) grains at the solid-liquid front in highly undercooled systems. Formation of dislocations at the solid-liquid interface and interference of density waves ahead of the crystallization front are responsible for the appearance of the new orientations at the growth front that lead to spherulite-like nanostructures.
Phase-field approach to polycrystalline solidification including heterogeneous and homogeneous nucleation
先进的相场技术已被应用于解决多晶凝固的各个方面，包括不同的晶体成核模式。通过求解相应的欧拉-拉格朗日方程，确定了成核势垒的高度。所示的例子包括比较各种模型的均匀晶体成核与原子模拟的单组分硬球流体。扩展了之前针对纯系统的工作（Granasy L、Pusztai T、Saylor D和Warren JA 2007 Phys. Rev. Lett. 98 Art No.035703）中，通过引入实现所需接触角的边界条件描述了一元和二元体系中的异质成核。单个颗粒的晶体学取向的四元数表示（在Pusztai T，Bortel G和Granasy L 2005 Europhys. Lett. 71131）已经被应用于模拟各种各样的多晶结构，包括晶体层、球晶和由具有树枝状、立方、菱形十二面体、截顶八面体生长形态的晶体构成的那些。最后，我们提出了说明性的结果枝晶多晶线凝固使用原子相场模型。
Nucleation suppression by charge screening on grain boundaries: a kinetic model for bulk imprint in polycrystalline ferroelectric thin films
Zhangjiang Laboratory（张江实验室）；Frontier Institute of Chip and System, Fudan University（复旦大学芯片与系统前沿研究院）；Institute of Microelectronics, Chinese Academy of Sciences（中国科学院微电子研究所）
Dynamic evolution of internal stress, grain growth, and crystallographic texture in arc-evaporated AlTiN thin films using in-situ synchrotron x-ray diffraction
The pyrochlore Ho2Ti2O7: Synthesis, crystal growth and stoichiometry
我们研究了合成和生长条件对烧绿石氧化物钛酸钬的磁性、结构和组成性质的影响，并证明了一种生长高质量化学计量比单晶的方法。在不同温度下合成了一系列具有不同Ti含量的多晶样品（-0.08 \leqslant x \leqslant 0.08，标称成分为Ho 2 Ti 2 + x O 7），并使用粉末X射线衍射进行表征。结果表明，在1500 °C的较高温度下合成粉末产生单相化合物。缺Ti粉末由于填充（Ho进入Ti位置）而显示晶格常数增加，而富Ti粉末由于反填充（Ti进入Ho位置）而显示晶格常数减小。发现在O2中的后退火对于完成抗填充过程是必要的。传统的浮区（FZ）技术的使用引入Ti不足，填充，和氧空位在生长的晶体。报道了用移动溶剂浮区法生长高结构质量、化学计量比的Ho_2Ti_2O_7单晶。交流磁化率的测量结果表明，化学计量比的晶体显示出较高的冰冻结温度，表明晶体质量和化学计量比起着关键的作用，该化合物的低温自旋冰性能。
Lattice Matching Dictates the Growth Mode and Quality of Deuterium Crystallization in Confined Spherical Shells
Southwest University of Science and Technology（西南科技大学）；Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所凝聚态物理国家实验室）；College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences（中国科学院大学材料科学与光电技术学院）；School of Materials and Chemistry, Southwest University of Science and Technology（西南科技大学材料与化学学院）；National Key Laboratory for Shock Wave and Detonation Physics Research, Institute of Fluid Physics, China Academy of Engineering Physics（中国工程物理研究院流体物理研究所冲击波与爆轰物理全国重点实验室）
