Surface plasmon polaritons (SPPs) that propagate in the nanometric metallic gap strongly depends on the gap-size. Nanometric optical waveguide circuits can be realized by using this characteristic of SPP. Nanometric optical waveguides based on this principle can be called surface plasmon gap waveguides (SPGWs). Basic characteristics of SPGWs have been reviewed by the three-dimensional (3D) numerical simulations. Applications of SPGWs to the practical devises in nano-photonics are also shown.

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The 10m and 3m semi anechoic chambers are in widespread use for the electromagnetic compatibility (EMC). The hybrid EM wave absorber consisting of the sintered ferrite tiles and the dielectric lossy materials has been usually used for these semi anechoic chambers. In the past, Suetake, Naito, and Shimizu's studies played a key part in providing the basis for the hybrid EM wave absorber. The reflectivity of the hybrid EM wave absorber can be calculated from the multi-layered approximate structure. Especially, each layer occupied partly the dielectric lossy materials can be replaced by the homogeneous plate having the equivalent relative complex permittivity, which is determined through the synthesized capacitance model in the large wavelength range. But, there was a problem that the equivalent relative complex permittivity differs with the process of the synthesized capacitance model.
We propose a new method which can be applied to the equivalent relative complex permittivity by the Finite Difference Method (FDM). Moreover, the reflectivity of the hybrid EM wave absorber using the thin corrugated dielectric lossy sheet is calculated and measured. As the result, it is confirmed that the measured reflectivity agree with the calculation one.

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A study to verify the effectiveness of the CIP method for analysis of the electromagnetic waves propagating in the 2D complex structure that a line source is located close to a concrete wall is presented. The results of theoretical analyses by the CIP method and those of our measurement using a scaled model of the target structure agree to a considerable degree with each other. The CIP method can be applied to analysis of the electromagnetic waves in the 2D structure even though reflection waves from the concrete wall highly affect the results. The effectiveness of the CIP method for analyzing the electromagnetic waves propagating in the 2D structure has been verified experimentally.

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A novel electron emitter utilizing the characteristics of ferroelectric ceramic materials has been developed. The electron-emitting portion of the electron emitter has a unique micro-structure which has the vacuum gap between an upper electrode and the surface of a ferroelectric layer. We confirmed electron emission by three-step process which consists of electron charge (the first step), charge retention (the second step) and electron emission (the third step). The ferroelectric hysteresis in the process indicates unique characteristics as follows. At the first step, remnant polarization of the same level as the completely adhered electrode structure is obtained in spite of a vacuum gap because the electron charge develops from the upper electrode to the surface of the ferroelectric layer under the vacuum gap in synchronism with the polarization reversal of the ferroelectric layer. In other hand, at the third step, the electric field in the vacuum gap advances electron emission while the development of the polarization reversal inhibits the return of the electron charge along the surface of the ferroelectric layer.

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The residual charge method is expected to be a powerful tool to detect the water tree degradation of polymer insulated power cables. In this method, DC voltage is firstly applied to electrify the degraded region. Some of the charges would be deeply trapped and stayed stably, even after the DC voltage is removed and the system is short circuited. AC voltage is subsequently applied in order to release the trapped charges. The DC component current, or the integration of it, is considered to have a correlation with the degree of degradation. This paper discusses the detail of the mechanism by which the DC component signal appears. The specimen was carefully prepared so that it contained water trees with uniform length. Space charge measurement was performed by pulsed electroacoustic method. The decay process of charges under AC voltages was interpreted into the energy depth at which the charge had been trapped, assuming that the charges were detrapped by the process of Poole-Frenkel type. It was suggested that the charges trapped between 0.8-1.2 eV can be detected as the DC component current. The shallower would be released by thermal energy at ambient temperature while the system was short circuited. The deeper would not be released by realistic AC voltages. The result showed that the transition of DC component current in the residual charge method represents the behavior of space charges having been trapped at deferent energy levels. It is believed that the results give useful information to apply the method to power cables.

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We have fabricated an optical polymer waveguide using plasma-enhanced polymerization. C₆H₆ and C₆H₁₀ are used as monomer materials for depositing core and cladding layer, respectively, because the refractive index of polymerized layers dominantly depend on the ratio of sp² and sp³ bond in those. By decreasing rf power less than 0.04 W/cm² dangling-bonds formed in a polymer film will be suppressed, so that a relative low loss waveguide has been fabricated. We have measured propagation loss of those waveguides in end-fire method by using laser light at 787 nm wavelength. The losses are 3.2 cm^-1 for the samples plasma-polymerized in Ar.

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Energy release from MIM structure of Al / nonpolar LB film / Au had continued for about three years, and temperature around MIM was reduced. In our present study, analyses were carried out on electrical properties of MIM of ultrathin polyimide LB film. Current, voltage and electrical power were analyzed in stationary state.

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In our present study, analysis were carried out on the voltage, current and electrical power released from MIM structure of Al/(C12TCNQ+BEDT-TTF) LB film/Au in the stationary state at room temperature (15-20)°C, especially on the electrical power released from above MIM structure.

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The RFID system in UHF band is a problem that deterioration of the radiation gain characteristic is caused by the attachment place of RFID tags. In this paper, we purpose to confirm the effect with some objects arranged in the back of the antenna in the RFID system. We carried out the study on changes of radiation gain characteristics when an antenna is attached a metal plate and when a magnetic lossy sheet is arranged between an antenna and a metal plate by analysis and measurement.

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Monte Carlo simulations have been done to elucidate influence of a sampling shutter on electron arrival-time spectra (ATS) in an electrical shutter drift tube experiment. It is revealed that the ATS profile at the collector electrode coincides with that at the first grid of the sampling shutter and the swarm parameters deduced from the spectra are not affected by transmissivity of the grid although the ATS profile changes depending on the transmissivity.

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