A low-threshold schottky barrier diode using natural pyrite has successfully been fabricated for the first time. The schottky and ohmic electrodes were successfully mounted and molded onto natural FeS₂(pyrite) crystals. The I-V characteristics of the devices were measured, and the typical Schottky barrier diode characteristics were confirmed. The barrier height estimated by fitting was shown to be as low as 0.60 eV, indicating that the device has low-threshold characteristics.

We examined the color change characteristics of two types of "Plasma Indicators" (referred to as Indicators hereinafter) irradiated by vacuum ultraviolet (VUV) light from excimer lamps. We found that the colors of both Indicators change in accordance with the sensitivity of the VUV irradiation dose when the oxygen concentration is constant. We concluded that an appropriate Indicator must be selected according to the required VUV irradiation dose of each excimer lamp application. Moreover, we demonstrated that both Indicators were useful, and the reproducibility of VUV irradiation was confirmed only under the same VUV irradiation conditions.

We fabricated electrogenerated chemiluminescence (ECL) cells having titanium dioxide nanoparticles (TiO₂ NPs) as an electron injection layer (EIL). The EIL paste, which was spin-coated on a cathode substrate, was annealed at three different temperatures of 250°C, 350°C, and 450°C. A tris(2,2'-bipyridine)ruthenium(II) solution was used as an emitter. The ECL performances were significantly increased with the increase in the annealing temperature. The 450°C-annealed cell showed the maximum luminance of 91.9 cd/m². By evaluating the crystalline structures and the surface chemical composition of the EIL, the improved performance was found to be attributed to the removal of undesired organic components from the EIL surface.

The common-mode antenna (CMA) model and the equivalent differential-mode (DM) circuit are based on the imbalance difference theory. The theory describes the mode conversion between the common mode (CM) and differential mode (DM) by focusing on the imbalance difference. The CMA model has been proven to provide excellent estimations of CM radiated emission. In this work, the CMA model is combined with the equivalent DM circuit to extend the CMA model to practical applications that include the mode conversion in both DM to CM and CM to DM directions and radiation loss. The combined model is applied to cable-connected printed circuit boards (PCBs) with an adjacent metal chassis that imitates a signal transmission system placed close to the metal chassis. The combined model calculated the CM radiated emission using a field-and-circuit co-simulator, considering the mode conversion in both directions and the radiation loss. Simulation results confirmed that the combined model precisely estimated the CM radiated emission by being separated from the DM radiated emission. The combined model also provided physical insights into EMC design that will enable the CM radiated emission to be efficiently reduced.

In order to realize a planar quadruplexer, we analyzed a dual-mode resonator based on a hairpin resonator, focusing on the resonant frequency and transmission zero. Using the analyzed resonator, four types of bandpass filters (BPFs) with different center frequencies were designed for use in a quadruplexer applying a microstrip line structure. The target passbands of each BPF are approximately 1.9 to 2.2 GHz, 2.3 to 2.6 GHz, 2.7 to 3.0 GHz, and 3.1 to 3.5 GHz, which are very close together. A matching circuit to connect the four BPFs was designed in order to realize a quadruplexer, and the circuit was analyzed using a circuit simulator and an electromagnetic simulator. The analytical results are in good agreement with the experimental results based on the microstrip line structure.

This paper proposes a new structure based on substrate integrated defected ground structure (SIDGS), and uses this structure to construct a compact triplexer with narrow bandwidth. Compared with the previous literatures related to the triplexer, the triplexer formed by this structure has a smaller size. In addition, the structure has good scalability and can be composed of any number of multiplexers without worrying about the coupling between the slots, which has favorable design flexibility. Moreover, the method of designing a multiplexer using this structure is also given, simulated, fabricated, and measured to prove the method's effectiveness.