Paruch P, Giamarchi T, Triscone J-M
DPMC, University of Geneva, Switzerland.
Phys Rev Lett. 2005 May 20;94(19):197601. doi: 10.1103/PhysRevLett.94.197601. Epub 2005 May 16.
The static configuration of ferroelectric domain walls was investigated using atomic force microscopy on epitaxial PbZr(0.2)Ti(0.8)O(3) thin films. Measurements of domain wall roughness reveal a power-law growth of the correlation function of relative displacements B(L) alpha L(2zeta) with zeta approximately 0.26 at short length scales L, followed by an apparent saturation at large L. In the same films, the dynamic exponent mu was found to be approximately 0.6 from independent measurements of domain wall creep. These results give an effective domain wall dimensionality of d = 2.5, in good agreement with theoretical calculations for a two-dimensional elastic interface in the presence of random-bond disorder and long-range dipolar interactions.
利用原子力显微镜对外延PbZr(0.2)Ti(0.8)O(3)薄膜中铁电畴壁的静态构型进行了研究。畴壁粗糙度的测量结果表明，在短长度尺度L下，相对位移相关函数B(L)∝L^(2ζ)呈现幂律增长，其中ζ约为0.26，随后在大L时出现明显饱和。在同一薄膜中，通过对畴壁蠕变的独立测量发现动力学指数μ约为0.6。这些结果给出了有效畴壁维度d = 2.5，与存在随机键无序和长程偶极相互作用的二维弹性界面的理论计算结果吻合良好。
