Applied Physics and Electronics

Our research work is focused on the optical properties and functions of nanoscale film structures and quantum structures (structures in which wave properties of electrons and holes appear) in semiconductors. Semiconductor nanoscale film structures are prepared using various physical vapor growth methods. We conduct advanced research into the various states of energy as well as the light emission mechanisms of the electron systems with the goal of developing guidelines to create new optical functions.

Laser light is playing an active role in familiar devices, such as light sources used in CD readers. These are used to create femtosecond pulse lasers [pulse width: 1-100 fs (from 10^(-15) to 10^(-13) seconds)]. The largest distance the light can travel during a single femtosecond is only 3 viruses (0.3 m). In this field, our research is mainly focused on studying the advanced mechanisms behind the generation of terahertz electromagnetic waves using this light.

There are many phenomena occurring constantly around us related to waves and vibrations, as well as many things which use these phenomena. We research the movement of electrons in regards to Light (lasers), terahertz waves, Plasmon and other electromagnetic waves, in regards to wave properties. We are working on creating new technologies combing usage of both light and electrons by understanding their combined behavior and function.

We are researching the optical properties and functions of semiconductor quantum dots (colloidal quantum dots) prepared by a hydrothermal method. We aim to understand the photoluminescence mechanism for quantum dots and apply it to new light-emitting materials.

Mathematical Engineering explores laws and universal principles that are hidden behind diverse and complicated phenomena. We are studying the state of quantum entanglement with group theory as well as engaging in research on metal-insulator transitions and magnetic transitions using the laws of the microscopic world. We are also researching nonlinear and non-equilibrium phenomena.

Using an ultra-high vacuum scanning tunneling microscope (UHV-STM), we can observe at the atomic level thin films and metal silicides of copper and nickel, familiar materials used in coins and other objects. We are also conducting fundamental research in regards to transistors and transparent conductive films made from organic semiconductors and which are fabricated on plastic substrates.

We explore novel probe beam technologies used in ultra-precise measurements of surface dynamic processes, such as adsorption, desorption, diffusion and ionization on an atomic scale. We also attempt to develop new methods of surface analysis by controlling the spin state of electrons involved in the ionization process at the interface, or by utilizing a focused ion beam.

Piezoelectric materials generate electricity when deformed or bent by external forces. The properties of these materials allow their application as sensitive elements, even in an environment with limited electric power. Currently, we are researching measurement technology for high-speed and high-energy particles using these materials.

The study of semiconductor devices on the boundary between science (semiconductor physics) and engineering (electronics). We are researching high efficiency solar cells, which are semiconductor devices that hold a high level of importance in our modern society, as well as wide-gap semiconductor devices.

We are working on the synthesis of new functional materials, the modification and analysis of existing materials which utilize plasma states in which atoms and molecules are ionized, and on the development of technologies for functional improvement and modification of certain materials. We are also developing technology to improve the stability of unstable organic semiconductor thin films by forming them using a method based on plasma polymerization.