Honeycomb nitrides layers as playground for Xenes formation

2021 年度 実施状況報告書

• 研究課題/領域番号: 21K04883
• 研究機関: 九州大学
• 研究代表者: Anton V.Visikovs 九州大学, 工学研究院, 助教 (70449487)
• 研究期間 (年度): 2021-04-01 – 2024-03-31
• キーワード: 2D material / honeycomb lattice / nitride / silicon carbide / spin-orbit interaction

研究実績の概要

In accordance with research plan from 2021 we have tried to prepare equipment and setting up experimental environment for growth of epitaxial silicon nitride on SiC(0001) and perform computational study of Xenes growth on that surface. The following results have been achieved:
1. One of the vacuum chamber equipped by LEED/RHEED analysis system is fully prepared for operation and silicon nitride growth.
2. XPS equipped chamber is brought to partial operational conditions after being transferred from another laboratory.
3. We have performed extensive computational study of Xenes formation on silicon nitride substrate using density functional theory (DTF) calculations. The stability of the structures has been investigated and showing promising results for future experiments. The electronic band structure of the Xenes also show interesting features related to topological properties and magnetic ordering.

現在までの達成度 (区分)

3: やや遅れている

理由

The experimental part of the project has been set back slightly due to technical issues. For example, the LEED/RHEED chamber sample holder has been broken and had to be repaired. LEED/RHEED chamber sample introduction system required redesign as previously used one had a major flaws associated with vacuum level degradation.
Current SiC sample preparation system experienced series of modifications.
Also the COVID pandemic situation prevented full extend of experimental work to be carried out.
The computational study on the other hand was proceeded as expected.

今後の研究の推進方策

The sample preparation optimization and direct experiment with growth of Xenes on nitride layer will be shifted to the next year. Other research activities are expected to be carried out in accordance with original research plan.

次年度使用額が生じた理由

As the research implementation, especially in experimental department, was slightly delayed due to technical and global pandemic reasons, only small amount of funds has been used. This is mainly in terms of direct commodity costs and also travel to collaborator's sites and discussing results in meetings. Next year we are planning to extend out research to full scale, plus additional work postponed from this fiscal year, therefore more supporting and operational funding will be required.
Particular plans include: (1) Further modification of experimental environment, (2) repairing malfunction commodities (some troubles with RHEED system and vacuum pumps), (3) Travel to collaborators site for STM/STS and ARPES measurements.