Development of high density quantum wire by interfacial dislocation array

2016 Fiscal Year Final Research Report

• Project/Area Number: 26420662
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Physical properties of metals/Metal-base materials
• Research Institution: The University of Tokyo
• Principal Investigator: Saito Mitsuhiro 東京大学, 大学院工学系研究科(工学部), 客員共同研究員 (00510546)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 転位 / 粒界 / 界面 / 電子顕微鏡 / 量子細線 / 酸化マグネシウム / 第一原理計算 / STEM

Outline of Final Research Achievements

We succeeded to form quantum wires with quantum properties embedded in a solid oxide crystal.
In this work, MgO bicrystal symmetrical tilt GBs were used as model system. The bicrystals were fabricated by joining two MgO single crystal blocks (including residual impurities) under high temperature.
Analyses of microstructure near the GBs revealed specific periodical structures. The atomic-resolution EELS elemental mapping revealed impurities segregation only at a coincidence site lattice (CSL) boundary which shows good lattice matching. The CSL GB showed that the Ca atoms are localized at the GB mirror plane, but Ti atoms exist at the neighboring sites (layer) of Ca sites. The detailed analysis and the theoretical calculation also revealed that co-existence and interaction of Ca and Ti atoms near the MgO GB with specific bonding angle might provide conductive Ti channels. By using dislocation technology, a quantum wire with quantum properties can be self-organized.

Free Research Field

結晶界面工学