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

布拉格科学院电介质系主任Hlinka博士表达了与谢菲尔德小组互动的强烈兴趣，并通过成为2010年4月至6月期间为期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大学新兴的拉曼活动，并在此过程中改善英国在这一关键结构确定领域的知识库。谢菲尔德大学的PI小组最近发现了一种新的AFE，基于nd掺杂BiFeO3 （BNF）的pbzro3结构陶瓷。与利兹大学合作，将很快开始使用脉冲激光沉积技术开发nd掺杂BiFeO3 （BNF）薄膜。这个新项目的最初目标是确定AFE结构是否保留在薄膜内，以及作为温度和成分的函数在散装中观察到的结构相变是否仍然有效。我们已经建立了拉曼光谱对BNF体系结构变化的敏感性，但这种新材料的主要问题是光谱的详细解释。因此，访问奖学金的主要研究目标是：1)建立实验方案，从薄功能薄膜中获得高质量的紫外拉曼光谱；2)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，将获得对BNF薄膜结构变化的完整理解，这将用于解释铁电和介电行为。除了这些科学目标之外，Hlinka博士还将讲授“在功能氧化物研究中使用振动光谱”的教程，并将访问英国功能氧化物社区内的几个感兴趣的团体。

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.