Materials design of quantum structures based on bicrystal technique and their high performances

2014 Fiscal Year Final Research Report

• Project/Area Number: 24686069
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Physical properties of metals
• Research Institution: Tohoku University
• Principal Investigator: WANG Zhongchang 東北大学, 原子分子材料科学高等研究機構, 准教授 (20510548)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: バイクリスタル / 電子顕微鏡 / 粒界 / 転位

Outline of Final Research Achievements

Dislocation defects together with their associated strain fields and segregated impurities are of considerable significance in many areas of materials science. However, their atomic-scale structures have remained extremely challenging to resolve. By developing a complex modeling approach in combination with bicrystal experiments and systematic atomic-resolution imaging, we are now able to pinpoint individual dislocation cores at the atomic scale, leading to the discovery of an unexpected phenomenon that even the simple magnesium oxide can exhibit polymorphism of core structures for a given dislocation species. These polymorphic cores are associated with local variations in strain fields, segregation of defects, and electronic states, adding instantly a new dimension to understanding the properties of dislocations in real materials. The findings advance our fundamental understanding of basic behaviors of dislocations.

Free Research Field

工学