Faraday's dream of the “magnetization of material by light” was realized by the invention of the laser. The appearance of ultrashort pulsed lasers has brought a new dream of “ultrafast and freely controlled magnetization.” In this review, the Faraday effect and the inverse Faraday effect, the Cotton-Mouton effect and the inverse Cotton-Mouton effect will be discussed. By using these inverse magneto-optical effects, I will show three dimensional vector control of magnetization employing three degrees of freedom of optical polarization. Polarization-, frequency-, pulse width-, and spatial shape-controlled light pulses will enable us more freely control magnetization.

Imaging in a high radiation environment is strongly demanded inside a nuclear plant. Image pickup tubes are more tolerant of the high radiation environment than semiconductor image sensors. However, it is difficult to fabricate compact and light image pickup tubes with low power consumption, because they use a thermal cathode. Recently, micro-field emitter arrays (FEAs) have been developed by microfabrication technology. The micro-field emitter is a tiny cold cathode, and easily integrated in arrays. When an FEA is used instead of a thermal cathode, FEA flat image pickup tubes with compactness, light weight, low power consumption and radiation tolerance can be developed. The paper describes the current status of the development of FEA flat image pickup tubes.

Some atoms that are added in small quantities greatly affect the characteristics of a material. For example, p- and n-type semiconductors are created by adding a small quantity of impurities in a semiconductor crystal. Therefore, research on these “active-sites” is very important to realize useful functions. However, no research has been performed concerning the question, “Where should the added atoms enter the material so that the function appears?” This is because the active-sites do not have a translational symmetry structure. Fortunately, in Japan, useful 3D atomic-imaging technologies have been developed recently. Hence a new project regarding “3D active-site science” has been launched. We hope the reader will collaborate with us to establish a new science of local active-site science.

A reliable technique for evaluating a barrier film, which is a key component used to encapsulate flexible organic light-emitting diodes (OLEDs), has been developed to reliably appraise the lifetimes of such devices. The water vapor transmission rate (WVTR) is commonly used as an index for a barrier film. Variables affecting WVTR measurements were investigated because results of such evaluations typically vary widely. Our standard films were used for comparative measurements to provide standard measurement procedures. Consistency between the systems in terms of the WVTR was achieved at a level of 10^-5 g m^-2 day^-1 at 40°C and 90%RH using the procedures. A reliable evaluation technique would encourage developments in high-barrier film fabrication for OLED encapsulation.

It is known that open air has moisture and it is not a controllable variable. To control an engine to accommodate a real-time humidity environment is very important to achieve better fuel economy and exhaust emissions. Ideas to measure and adjust engine control are not new, but they have not been carried out for a long time because a suitable automotive humidity sensor did not exist. Today, highly accurate and highly reliable humidity sensors using MEMS technology have been launched by the automotive industry. In parallel, global market needs are shifting to fuel economy performance and environmentally-friendly emission levels. In this paper, trends in engine control systems adapted to humidity sensing are described.

The three-dimensional structure of a metamaterial is indispensable to realize isotropic optical metamaterials. As a fabrication technique for such a three-dimensional metamaterial with a large area, we developed a novel fabrication method that combines electron beam lithography and the self-organized formation of a resonator ring using the residual stress of meta-thin films. An effective index of 0.35, which is lower than that of a vacuum, was experimentally obtained at 30THz.

Compact high voltage power switches are highly desirable for intelligent power grids with renewable energy sources. As this infrastructure develops, the requirements for such electronics will increase dramatically. In particular, reliable compact high voltage switches that can operate at over 100kV will be in high demand. This report introduces research to develop a novel semiconductor-vacuum switch utilizing the insulation capability of a vacuum and the unique properties of a diamond semiconductor, which could meet such difficult demands.

This article provides an introduction to the basics of vacuum science and technology. Firstly, the definition of a “vacuum” is given, and the kinetic theory of gases is briefly described. Secondly, the operation principles are explained for several popular types of vacuum pumps, i.e., a rotary pump, a turbomolecular pump, and a cryopump. Caution points for using vacuum pumps are also given. Because this article covers only a limited part of the wide range of vacuum technology, the readers are encouraged to read the more extensive literature for the operation of actual vacuum systems.