Outcome：

2023
By comparing passivation capping by ZnO and AlOx, it was found that the crytallinity of the formed film and the self-cleaning process of the precursors play an important role in determining the properties of the surface quantum dots.

2022
By passivating surface InAs quantum dots, enhanced PL intensity with reduced wavelength peak was obtained.

Outcome：

2023
While the fundamental investigation has been concluded by FY 2022, the knowledge accumulated is being applied for controlling defects particularly in growth of lattice mismatched materials.

2022
Exploration of novel devices are begin performed based on the information about defects in GaAs we have elucidated.

MBE growth of InGaAs quantum structures using submonolayer (SML) stacking is studied thereby precisely controlling the structure and electronic properties of the quantum structures.
Further, the potential of applying such structures to spintronics is investigated.

Outcome：

2023
Control of spin was shown by illuminating these 2D and 3D structures by circular polarized excitation light.

2022
The transition of 2D-3D in submonolayer growth has been studied and the critical conditions were identified and the mechanisms were studied.

Outcome：

2023
Shown that quantum discs can be prepared by using SML stacking.

2022
Preparation of quantum discs that are considered to be a strong candidate for photon upconversion is being investigated.

Outcome：

2023
By comparing different precursor materials, the basic guidelines for passivating InAs surface quantum dots were proposed.

2022
The recipes and the mechanisms of passivating InAs surface quantum dots were studied.

Outcome：

2023
Controlled growth of 2D and 3D quantum structures by SML stack growth has been successfully demonstrated, and its device applications are under investigation.

2022
The transition of 2D-3D in submonolayer (SML) stack growth has been studied and the critical conditions were identified and the mechanisms were studied.

Outcome：

2023
Strain-free passivation capping of surface quantum dots by ALD metal oxide thin films was successfully demonstrated, and its device applications are under investigation.

2022
Atomic layer deposition (ALD) of metal oxide thin films are being investigated.

An attempt to realize short wavelength emission from oxide thin films.

Outcome：

2023
Organizing the lab/equipment for improving the films.

2022
Short wavelength light emission from oxide films indicated.

Submonolayer (SML) deposition by MBE is a method that was proposed to assembled InAs nanostructure while maintaining 2D (layer-by-layer) growth. However, it has recently been shown that under certain growth conditions, a transition from 2D to 3D growth regime occurs during SML growth. This process is interesting for both fundamental physics and potential applications.

Outcome：

2023
We were able to investigate various factors that affect the 2D to 3D transition during SML growth. Some of the results have been presented in the JSAP Autumn Meeting 2023.

Indium arsenide surface quantum dots offer size-dependent spectral emission, surface charge accumulation, and a significant surface-to-volume ratio, making them promising for gas/chemical monitoring. In my research, I've developed methods to prepare high-density InAs SQD samples, enhancing their sensitivity to adsorbed chemical species on the surface.

Outcome：

2023
私の研究では、高密度 InAs SQD サンプルを調製し、表面に吸着された化学種に対する感度を高める方法を開発しました。 これらの発見は、SSDM および JSAP カンファレンスで発表されました。シミュレーション ソフトウェアを使用して、SQD の波動関数を調整してより多くの表面積を効果的にカバーし、それによって感度を増幅できる可能性をさらに実証しました。 このセクションの結果は、3 つの要約として ICMBE 会議に提出されました。私は、波動関数による密度と表面被覆率が異なる吸着化学種との相互作用に対する SQD の感度をテストするために、ガス室とフォトルミネッセンスのセットアップを構築しました。 この研究の結果はユニークであり、これほど詳細に報告されたことはなかったので、私はACSの出版物がこれらの結果を数か月以内に発表することを目指してきました。