Æü»þ: |
2013-06-14 13:30 - 14:30 |
¾ì½ê: |
4¹æ´Û2³¬Îعּ¼1¡¢Å쳤1¹æ´Û324¼¼ |
²ñµÄ̾: |
ʪ¹½¸¦ÃÌÏòñ¡Ê13-08¡ËMeasurement of Topological Structure in Amorphous Solids using Coherent Diffraction |
Ï¢ÍíÀè: |
·§°æÎè»ù¡¡6024 |
¹Ö±é¼Ô: |
Dr. J. Murray Gibson (Department of Physics, Northeastern University) |
¹Ö±é¸À¸ì: |
±Ñ¸ì |
¥¢¥Ö¥¹¥È¥é¥¯¥È: |
Glasses and other amorphous solids are widely used for their mechanical, optical and electronic properties, yet the correlation between properties and structure is poorly understood. One missing link is¡Èmedium-range-order¡É (MRO) which often arises from topological atomic structure. While important to properties, MRO has been notoriously hard to study because conventional diffraction gives only short-range order. Using coherent diffraction techniques such as Fluctuation Electron Microscopy (FEM)(1) , this problem can be solved. We describe the techniques and its applications to amorphous semiconductors in detail. The use of transmission electron diffraction and x-ray diffraction is discussed. We also review some other applications, including the promise of FEM¡Çs use in studying partially-ordered organic and biological systems. (1) Gibson, J. M.; Treacy, M. M. J.; Sun, T.; et al., Phys. Rev. Lett., 105 , p125504 (2012). |
|