Raman spectroscopy of Nd-doped BiFeO3 based ceramics and thin films

布拉格科学院饮食系主任Hlinka博士表达了与谢菲尔德团队互动的强烈兴趣，并希望通过在2010年4月至6月期间担任3个月的客座教授来建立尽可能强大的合作。这一合作将极大地推动谢菲尔德蓬勃发展的拉曼活动，并通过这样做改善英国在这一关键结构确定领域的知识基础。谢菲尔德的PI小组最近发现了一种新的AFE，即基于掺钕BiFeO_3(BNF)的PbZrO_3结构陶瓷。与利兹大学合作，使用脉冲激光沉积的掺钕BiFeO_3(BNF)薄膜的开发工作将很快开始。这一新计划的最初目标将是确定AFE结构是否保留在薄膜中，以及作为温度和成分的函数而大量观察到的结构相变是否仍然有效。我们已经证实，拉曼光谱对BNF体系中的结构变化是敏感的，但这种新材料的主要问题是对光谱的详细解释。因此，访问研究员的主要研究目标是i)建立从薄膜功能薄膜中获得高质量紫外拉曼光谱的实验方案，以及ii)利用Hlinka博士的丰富经验来帮助解释光谱。除了拉曼研究外，PI小组还将使用分析电子显微镜(EP/F006098/1，S.Miao)获得详细的结构信息。通过这种方式，我们将对BNF薄膜的结构变化有一个完整的了解，这将被用来解释铁电和介电行为。除了这些科学目标，Hlinka博士还将讲授“振动光谱在功能氧化物研究中的应用”的教程，并将访问英国功能氧化物社区内的几个感兴趣的组织。

Dr Hlinka, Head of the Department of Dieletrics at the Academy of Science, Prague, has expressed a strong interest to interact with the Sheffield group and to establish the strongest possible collaboration by becoming a Visiting Professor for a period of 3 months between April-June 2010. This collaboration would hugely advance the burgeoning Raman activity at Sheffield and in doing so improve the knowledge base for the UK in this key area of structural determination. The group of the PI at Sheffield have recently discovered a new AFE, PbZrO3-structured ceramic based on Nd-doped BiFeO3 (BNF). In collaboration with the University of Leeds, the development of thin films of Nd-doped BiFeO3 (BNF) using pulsed laser deposition will shortly begin. The initial aims of this new programme will be to establish whether the AFE structure is retained within the film and whether the structural phase transitions observed in bulk as a function of temperature and composition remain valid. We have established that Raman spectroscopy is sensitive to the structural changes within BNF system but the main problem with such new materials is in the detailed interpretation of the spectra. The key research goals of the Visiting Fellowship are therefore to i) establish the experimental protocols to obtain high quality UV Raman spectra from thin functional films and ii) utilise the vast experience of Dr Hlinka to help interpret the spectra. In addition to the Raman study, the group of the PI will obtain detailed structural information using analytical electron microscopy (EP/F006098/1, S.Miao). In this manner, a complete understanding of the structural changes in BNF thin films will be obtained which will be utilised to interpret the ferroelectric and dielectric behaviour. In addition to these scientific goals, Dr Hlinka will give tutorials on the 'Use of Vibrational Spectroscopy in the Study of Functional Oxides' and will visit several interested groups within the UK Functional Oxide community.