Research Institute of Electrical Communication, Tohoku University
Center for Nation-Wide Cooperative Research on ICT

Electron Transport Through Single Nanocrystals Coupled to Nanogap Metal Leads

SHIBATA KenjiProfessor

Faculty of Engineering, Tohoku Institute of Technology

Control and understanding of the carrier transport in colloidal quantum dots (CQDs) is crucial for device applications. However, due to the fluctuations in the size and morphology of CQD arrays, characterizing carrier transport has been challenging. In this work, we investigated the carrier transport through a single CQD coupled to nanogap metal electrodes. We measured single electron tunneling through the CQDs and observed quantum dot size-dependent carrier transport, a large charging energy, orbital-dependent electron charging energy and conductance, electric field modulation of the electron confinement potential, and the Kondo effect, which provide nanoscopic insights into the carrier transport through CQDs at the single quantum dot level. These findings make CQDs promising for future development of optoelectronic and quantum information devices, particularly room-temperature single-electron transistors with excellent optical properties.

[Keywords] Colloidal quantum dots, Single electron transistors, Quantum effects

Analysis of Parallel Simulated Annealing Algorithms Based on Probabilistic Bits

KOSHITA ShunsukeAssociate Professor

Faculty of Engineering, Hachinohe Institute of Technology

Probabilistic bits (p-bits) are expected to be next-generation low-power devices. However when p-bits are applied to parallel computing algorithms, there arises a significant degradation in accuracy. Although this issue is attributed to the oscillation phenomenon of p-bits, the mechanism of this oscillation remains unclear. In this study, we theoretically analyze the behavior of p-bits in parallel annealing algorithms with the aim to reveal the conditions for prevention of p-bit oscillations.

[Keywords] Probabilistic bit, Parallel simulated annealing algorithm, Oscillation

Toward the Realization of Information Infrastructure Supporting Smart Society

KITAGATA Gen Professor

Faculty of Humanities, Morioka University

Our research group has been conducting R&D on information flow, multi-agent, networking, and AI-based sensing and analysis technologies, aiming to realize a next-generation computing infrastructure for IoT that supports a smart society. In this presentation, we will introduce the results of these R&D activities and report on our efforts to realize a smart society.

[Keywords] IoT, Smart Society, ICT

Silicon Photonics - Heterogeneously Integrated Laser

KITA Tomohiro Professor

Faculty of Science and Engineering, Waseda University

The heterogeneously integrated laser diodes, which combines a high-performance external cavity fabricated using silicon photonics with a compound semiconductor, enables the integration of various functionalities by utilizing passive wavelength filters, optical switches, optical modulators, and photodetectors available in silicon photonics. In this presentation, research on compact and low-power LiDAR and THz-wave transmitters using high-performance heterogeneously integrated lasers will be introduced.

[Keywords] Heterogeneous, Integration Silicon Photonics, Photonic-electronic integration

Development of Atmospheric Pressure Air Plasma Application Technology for Lunar Farms

KANEKO Toshiro Professor

Graduate School of Engineering, Tohoku University

Locally procuring fertilizer is a major issue when cultivating crops on the moon. In particular, nitrogen fertilizer is lacking in the composition of lunar sand (lunar regolith), so nitrogen fixation technology using air plasma is attracting attention. We have developed a method to synthesize dinitrogen pentoxide (N₂O₅) using an atmospheric pressure air plasma. N₂O₅ dissolves in water, converting to nitrate (NO₃-), a key nitrogen fertilizer. Our experiments demonstrated that the N₂O₅ dissolved solution exhibited nitrogen fertilization effects, even in a simulated lunar regolith environment, enabling the continuous growth of rice plants. This innovative technology holds great promise for enhancing the sustainability of lunar agriculture.

[Keywords] Atmospheric pressure air plasma, Nitrogen fixation, Lunar farm

 Inter-organizational Collaboration Project 

Immersive Digital Twin for Scientific Workflow and Industry 4.0

WANG RuiSenior Research Scientist

Commonwealth Scientific and Industrial Research Organisation(CSIRO), Australia

Digital Twin systems, which consists computational models and simulations, have become valuable tools for advancing both scientific research and industry innovation, offering a cost-effective and scalable way to replicate real-world experiments. However, accurately capturing the complexities of physical environments through AI-assisted simulations remains a challenge. This presentation explores our early efforts in integrating eXtended Reality (XR) interfaces within AI-driven Digital Twin systems to enhance the fidelity, usability, and scientific accuracy of experimental simulations. By incorporating multi-dimensional visualisation, full-scale simulation, first-person perspective, and natural interactions, this innovative approach bridges the gap between physical and digital environments. Through our early-stage exploration, we provide a forward-looking perspective on how immersive Digital Twin systems will create transformative impacts on both scientific workflows and Industry 4.0, enabling more precise experimentation and deeper insights into complex phenomena.

[Keywords] Digital Twin, EXtended Reality (XR), Industry 4.0