Crossover of the roughness exponent for interface growth in systems with long-range interactions due to lattice distortion
Crossover of the roughness exponent for interface growth in systems with long-range interactions due to lattice distortion
复制标题
由于晶格畸变而具有长程相互作用的系统中界面生长的粗糙度指数的交叉
DOI：
10.1103/physrevb.88.094303
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
S. Miyashita
中科院分区：
文献类型：
--
作者：
M. Nishino;T. Nakada;C. Enachescu;K. Boukheddaden;S. Miyashita
我们研究了由晶格畸变引起的长程相互作用系统中的畴壁传播。当分子单元的局部双稳态具有不同的尺寸时，例如，高自旋和低自旋态的自旋交叉系统中，弹性畸变导致有效的长程相互作用。在这种系统中有序态之间的切换过程中，畴壁存在两个自由度，即一个相对于晶格结构，另一个相对于自旋（电子）态。晶格畴壁的界面宽度与系统尺寸成正比，反映了长程相互作用的宏观结构，而自旋态的界面宽度则随自旋态和晶格动力学的相对时间尺度的不同而呈现出不同的特征.当自旋态变化较快且晶格弛豫不充分时，二维短程相互作用系统生长模型中普遍存在的粗糙度指数相反，当晶格充分弛豫时，自旋界面与晶格界面相同，即，。我们分析了系统的压力场，发现通过长程相互作用使压力场平衡是导致1/2和1之间的过渡的关键。
We study domain wall propagation in systems with long-range interactions caused by lattice distortion. When the local bistable states of the molecular unit have different sizes, e.g., high-spin and low-spin states in spin-crossover systems, the elastic distortion causes an effective long-range interaction. In switching processes between the ordered states in such systems, there exist two degrees of freedom for the domain wall, that is, one with respect to lattice structure and the other to a bistable spin (electronic) state. The interface width of the lattice domain wall is proportional to the system size, which reflects the macroscopic structure due to the long-range interaction, while the interface width of the spin state shows different characteristics depending on the relative time scales of dynamics of the spin state and the lattice. When the change of the spin state is relatively fast and the lattice relaxation is insufficient, the roughness exponentis, which has been commonly found in growth models of short-range interaction systems in two dimensions. In contrast, when the lattice relaxes sufficiently,of the spin interface is the same as that of the lattice interface, i.e.,. We analyze the pressure field of the systems and find that the equilibration of the field via the long-range interaction plays a key role in the mechanism of the crossover ofbetween 1/2 and 1.