主讲人： 孙力

时  间： 2011.03.24日 1:00 PM; 03.25日 9:30 AM; 03.25日 1:00 PM;

         03.26日 9:30 AM; 03.26日 1:00 PM;

地  点： 教三楼226

Abstract：

This five-part seminar serial will present an overview of several fundamental material science concepts as well as the development of modern material synthesis and characterization techniques. The goal of these lectures is to provide information, stimulate discussions and develop collaborations..

Part I. Application of x-ray diffraction techniques in materials research.

X-ray diffraction can provide a wide range of material structure information that is critical for material scientists. In addition to the conventional x-ray powder diffraction (q-2q scan), this lecture will introduce the small angle, texture (pole-figure), rocking curve, grazing incident diffraction and phase transformation x-ray techniques. Examples of using x-ray to determine materials composition, crystal structure, orientation and microstructure will be provided. Also the lecture will discuss our recent research on using x-ray synchrotron radiation to perform real time in situ study of metal electrodeposition to study material nucleation, growth and nuclei stability at the nano-scale.

Part II. III Nanomagnetics

This two part lecture will cover the fundamental concepts of magnetism and novel magnetic phenomenon in artificial magnetic nanostructure. First part of the presentation will go over the fundamentals of magnetism. We will discuss both the intrinsic and extrinsic magnetic properties of materials. Use magnetic nanowires as an example, we will demonstrate how magnetic properties of materials can be designed and tuned by nanofabrication. We will also discuss the novel magnetic phenomena such as giant magnetor resistance (GMR) and exchange bias (EB) that only exist in artificial magnetic nanostructures. These two phenomena laid the foundation for the development of spin valve structure that modernize the magnetic field sensor. Magnetic anisotropy, size effects and magnetization rotation models will be reviewed.

Part IV. Thin films-fabrication

Thin films form the most important functional components in many devices. With the technological advancements, a wide range of physical and chemical methods have been developed for thin film fabrication. This lecture will provide an overview of different thin film synthesis techniques and their mechanisms. The lecture will look at representative physical and chemical thin film synthesis methods and discuss the advantages and disadvantages associated with each individual method.

Part V. Nanofabrication and materials characterization

Nanoscience and technology as an emerging interdisciplinary research area has caught a lot of attention in recent years. A general overview of the history, current status and available techniques will show that although a wide range of nanomaterials with novel properties that does not exist in bulk samples can now be synthesized; there is still a long way for nanoscience and nanotechnology to direct impact our everyday live. A lot of work need to be done to improve nanomaterials fabrication reproducibility and quality control; improve nanomaterials outpout and reduce cost; understand coupled nano-phenomena; and integrate nanomaterials with existing technology and devices. Along with the development of various nanomaterial synthesis methods, the materials characterization techniques also advanced dramatically in recent years. This lecture will also go through the basics of microscopy, diffraction, and spectroscopic techniques for material characterization.

Bio

Dr. Li Sun is currently the Bill D. Cook endowed Associate Professor of Materials and Mechanical Engineering at the University of Houston. He obtained his PhD degree in Materials Science and Engineering from the Johns Hopkins University in 2002. He got his BS degree in Physics from Nanjing University in 1993. Dr. Sun’s research focuses on advanced functional materials synthesis and device application. His current research projects include magnetic nanomaterials synthesis, manipulation and biomedical applications; nano-magnetics; and nanomanufacturing of ferroelectric devices and multifunctional nanocomposites for bio-sensing. He has published more than 60 SCI journal papers with over 900 citations.