Conical light scattering in strontium barium niobate crystals related to an intrinsic composition inhomogeneity
Conical light scattering in strontium barium niobate crystals related to an intrinsic composition inhomogeneity
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DOI：
10.1088/0953-8984/19/15/156225
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发表时间：
2007-03
期刊：
影响因子：
--
通讯作者：
K. Bastwöste;U. Sander;M. Imlau
中科院分区：
文献类型：
--
作者：
K. Bastwöste;U. Sander;M. Imlau
在宽温度范围内，多域和单域、标称纯的、Eu 掺杂的铌酸锶钡 (SBN) 晶体中都发现了锥形光散射。观察到两个散射锥体、一条散射线和一个电晕的出现，并且可以在埃瓦尔德球概念内全面解释。光折射、来自域边界或生长条纹的散射可以被排除在解释散射起源之外。结果表明，温度持续散射过程与生长诱导的接种棒有关，即主要位于 SBN 样品中心的成分不均匀性。棒的方向平行于 c 轴，并在微观尺度上产生随空间频率的折射率不均匀性。
Conical light scattering is uncovered in poly- and mono-domain, nominally pure and Eu-doped strontium barium niobate (SBN) crystals over a wide temperature regime. The appearance of two scattering cones, a scattering line and a corona is observed and can be explained comprehensively within the Ewald sphere concept. Photorefraction, scattering from domain boundaries or from growth striations can be excluded from explaining the origin of the scattering. It is shown that the temperature-persistent scattering process is related to a growth-induced seeding rod, i.e. a composition inhomogeneity primarily localized at the centre of the SBN sample. The rod is directed parallel to the c axis and yields a refractive-index inhomogeneity with spatial frequencies on the micro-scale.