On the influence of wall microdeformations on Bloch line visibility in bubble garnets (invited)
On the influence of wall microdeformations on Bloch line visibility in bubble garnets (invited)
复制标题
气泡石榴石壁面微变形对布洛赫线可见度的影响（特邀）
DOI：
10.1063/1.347777
复制
发表时间：
1991
影响因子：
3.2
通讯作者：
J. Miltat
中科院分区：
文献类型：
--
作者：
A. Thiaville;J. Youssef;Y. Nakatani;J. Miltat
提出了在各向异性暗场光学成像中，泡状石榴石中垂直布洛赫线（VBLs）对比的主要来源是线位置壁面的微变形。壁面倾斜的动力是对vbl所携带的单极σ电荷的补偿。倾斜的壁段作为一个相位对象，允许形成具有良好定义的对称性和独立于入射光束偏振的线像。所有这些特征都与实验证据完全吻合。本文给出了一个壁面变形的近似模型，并证明在给定厚度和材料参数下，壁面变形的近似模型与VBL三维结构的从头计算结果是一致的。分析了微变形模型在线可观测性方面的意义，并与实验数据进行了比较。
It is proposed that the main source of contrast of vertical Bloch lines (VBLs) in bubble garnets, when viewed by means of anisotropic dark field optical imaging, is a microdeformation of the wall plane at line location. The motive force for wall tilting is the compensation of the monopolar σ charges borne by VBLs. The tilted wall section acts as a phase object and allows for the formation of line images with well‐defined symmetries and independent of the incident‐beam polarization. All these features agree fully with experimental evidence. An approximate model of the wall deformation is presented and shown to be consistent for a given thickness and material parameters with the results of an ab initio numerical computation of the 3D structure of a VBL. The implications of the microdeformation model in terms of line observability are analyzed and compared with experimental data.