Department of Energy Engineering

Electrical and Energy System Engineering Division

Overview

Corresponding to the rapid development of advanced electronics and information technology while envisioning the future of these fields, our laboratory educates and conducts research to explore the fundamental electronic properties and new phenomena of materials such as semiconductors and dielectrics, and develops new electronics-related materials with applications in devices. Furthermore, our goals are to generate efficient electrical energy on the basis of those developed materials; to promote advanced technological development of transportation and energy conversion; to conduct basic analysis on the nature and representation of information; and to build control systems based on the fundamental theories of information processing and transmission techniques of computer hardware and software technologies.

Laboratory introduction

For faculty member details, please see the staff introductions.

Laboratory	Semiconductor, nanomaterial engineering
Faculty members	Professor ITO Takashi Assistant professor YAMADA Shigeru
Research details	Aiming to realize highly-efficient solar cells and high-capacity power storage elements, our laboratory conducts research ranging from the fundamentals to applications in semiconductors and nanocarbon materials in order to develop new evaluation techniques of solar cells and evaluate cells therewith, to develop solar cells with quantum structures, and to produce nanocarbon materials and their applications in power storage elements.

Laboratory	Lightning, lightning protection measures
Faculty members	Professor TAKAGI Nobuyuki Professor WANG Daohong Assistant professor WU Ting
Research details	More than half of accidents that occur within the electrical power grid system are caused by lightning strikes. Also, lightning strike accidents frequently happen to wind turbine generator systems, which have been receiving increased attention recently. Our laboratory has accepted the challenge of developing techniques for monitoring, predicting, and controlling lightning discharges, through various observations and experimentation, in order to establish more complete countermeasures against such accidents.

Laboratory	Radar remote sensing
Faculty members	Professor KIMURA Hiroshi
Research details	With regard to remote sensing techniques for observations of the surface of the Earth using imaging radar installed on satellites and aircraft, our laboratory conducts research to develop and improve data processing and analytical techniques (in particular, interferometry and polarized wave measuring methods) that assist monitoring global environments, and to understand the correlation between radar radio scattering and observation data of an object on the ground.

Laboratory	Science of high-pressure extremes of physical properties
Faculty members	Professor SASAKI Shigeo
Research details	Our laboratory causes new phenomena of electronic properties by driving various substances forcibly into extreme situations under ultra-high pressure and elucidates the physical properties of those phenomena using Raman and Brillouin scattering, electrical conductivity, dielectric constant measurements, and other techniques. In addition, based on results obtained utilizing ultra-high pressure generation techniques, we conduct basic research to develop new dielectrics, ion conductors, and superconducting materials, etc.

Laboratory	Integrated circuits, communication subsystems
Faculty members	Professor NAKAMURA Makoto Assistant professor ITO Daisuke
Research details	Aiming at upgrading information and communication systems that support an advanced information society, our laboratory conducts research from the fundamentals to final applications in order to: realize high-speed, power-saving, optical-receiving circuits; power-conserving and highly-efficient optical transmitting and receiving circuits for optical packet transmission; and highly-functional optical receiving circuits with digital controls.

Laboratory	Solar cell development, device simulation
Faculty members	Professor FUJIWARA Hiroyuki
Research details	With the intention of solving global energy and environmental issues, our laboratory engages in developing new solar cell materials by utilizing computational engineering and establishing versatile device simulation technologies. In particular, we conduct comprehensive studies that cover the basic physical properties of materials, and develop rigorous simulation technologies for solar cell devices. Our laboratory performs experiments and theoretical calculations to clarify light absorption characteristics of various solar cell semiconductor layers in an integrated manner. Furthermore, we have developed a solar cell simulator (e-ARC method) that applies these new analytical techniques, and provide it free of charge via the Internet.

Laboratory	Laser engineering, renewable energy
Faculty members	Professor YOSHIDA Hiroki Assistant professor KAMEYAMA Nobukazu
Research details	Our laboratory conducts research of laser measurements, laser processing, laser nuclear fusion, and laser atmospheric propagation, as well as related operating efficiencies utilizing machine learning applied to renewable energy and new energy sources with less environmental impact.

Laboratory	Power electronics
Faculty members	Professor ISHIKAWA Hiroki
Research details	Our laboratory studies power generation, power storage, and energy conservation in order to solve energy issues utilizing power electronics technologies that convert electrical power via semiconductor switching operations. The main research themes include simulation technologies of high-performance drive control systems, semiconductor power conversion systems, photovoltaic and wind power generation systems, and power electronics systems of various motors, with their related applications.

Laboratory	Ferroelectric physical properties
Faculty members	Associate professor OHWA Hidehiro
Research details	Ferroelectrics are important electronic materials that are utilized in our immediate surroundings, such as sensors, actuators, ultrasonic transducers, and FeRAM. Aiming for the improved performance of materials, our laboratory engages in creating new single crystal ferroelectrics and ceramics by performing measurements of the basic physical properties such as the dielectric characteristics, piezoelectric properties, P-E hysteresis curves, and domain observations, and conducting research using lead-free, environmentally-friendly materials.

Laboratory	Integrated circuit systems
Faculty members	Associate professor TAKAHASHI Yasuhiro
Research details	Recently, due to technological advancements of the manufacturing process of very large scale integration circuitry (VLSI), the operating speeds of VLSI circuits have been increasing. On the other hand, as VLSI chips operate at higher speeds, heat production due to the LSI increases accordingly. Both VLSI and the generated heat significantly affect the other electronic components. If we achieve VLSI that operates at high speed without generating heat, this technology can be applied everywhere in the world. Our laboratory intends to design just such VLSI with low power consumption and high-speed operation using a circuit-level approach. In particular, we have been primarily studying adiabatic logic to reduce power consumption by replacing conventional DC voltage and operating VLSI with AC voltage. We believe that adiabatic logic is a promising technology for circuitry that can contribute to the present ecology of society.

Laboratory	Information systems engineering
Faculty members	Associate professor HAMADA Kazuyasu Assistant professor SUZUKI Tatsuo
Research details	Our laboratory studies mathematical theory that is fundamental to systems and controls. In particular, students conduct research consisting mainly of two categories: computer science, systems, and electronic circuits; and, the associated controls.

Laboratory	Fundamental properties of photofunctional semiconductor materials and their applications
Faculty members	Associate professor HAYASHI Koji
Research details	Our laboratory focuses on photosensitive semiconductor materials such as amorphous crystals and nanocrystals, which are expected to be applied in optical memory and optical sensors, imaging tubes, solar cells, etc. With the goal of applying these materials in optical devices, we study the basic optical and electrical properties of semiconductors with various types of light, using spectrums in the ultraviolet, visible, and infrared regions, and high-energy synchrotron radiation.

Laboratory	Millimeter wavelength, terahertz wavelength photonics
Faculty members	Associate professor HISATAKE Shintaro
Research details	Based on photonics technology, our laboratory is developing a technique to visualize electromagnetic waves of millimeter wavelengths and terahertz wavelengths of 30 GHz to 10 THz. Using this technique, we have been working on the evaluation of 79 GHz millimeter wavelengths used in on-vehicle radar, analyses of millimeter and terahertz wireless communication paths, experimental study of electromagnetic responses of metamaterial and plasmonic devices, and experimental study of scattering and diffraction of optical vortex and non-diffraction beams.

Laboratory	Magnetic materials, magnetic measurements, dissimilar material joining
Faculty members	Associate professor YUN Kyyoul
Research details	Domestic power consumption in Japan is presently 999.6 billion kWh, with 57.3% consumed by rotating machines, and in particular, motors. Reducing power losses from rotating machines enables increases in efficiency utilizing electrical energy, leading to electrical energy conservation, and ultimately realizes negawatt power. It is possible to create reliable, light weight, and strong materials by joining dissimilar metals of high specific strength to high strength structural material. It is known that reducing vehicle weight by 30% enables a decrease in fuel consumption of 20%, which would significantly contribute to conserving energy.

Laboratory	Electrical power systems
Faculty members	Associate professor TAKANO Hirotaka
Research details	Electrical power and energy systems are expected to achieve high levels of six indices: quality, reliability, stability, safety, economy, and environmental adaptability. Our laboratory aims to design and introduce to society an electrical power system that satisfies and enables co-existence of both suppliers and consumers by exploring technologies that realize advanced energy management.