Daiki KOIDE Shouta KATO Eri IKEDA Nobuyuki IWATA Hiroshi YAMAMOTO
The purpose of this work is to synthesize a three-dimension C60 polymer using photo-polymerization method. The used pristine materials were C60 precipitates prepared by a liquid-liquid interfacial precipitation (LLIP) method. The prepared LLIP material was set in the vacuum and was compressed in the anvil with the pressure of 600 MPa or 7 GPa. The 4th harmonics FEL with the wavelength of 500 nm was irradiated with macro-pulses (the pulse width of 20 µs) containing very short micro-pulses (the pulse width of 200 fs). The Raman Ag(2) peak of C60 molecules in the vicinity of 1469 cm-1 becomes broad and shifts to the lower energy region as proceeding of polymerization. Under high pressure and/or FEL irradiation the LLIP crystal revealed the large red-shift and the increment of the half width of the Raman Ag(2) peak. Furthermore the LLIP crystal mixture with iodine revealed the more distinctive red-shift, ca.13cm-1 because of highly packing of C60 molecules. The C60 molecular accession by LLIP process and/or the photo-assisted hole-doping from iodine were promising conditions to promote the photo-polymerization effectively.
Ryo MIYAZAWA Dai TAGUCHI Takaaki MANAKA Mitsumasa IWAMOTO
By using electric field induced second harmonic generation (EFISHG) and Capacitance-Voltage (C-V) measurements, we studied carrier behaviors in ITO/polyimide (PI)/poly(3-hexylthiophene)(P3HT)/Au diodes. Photoillumination caused the threshold voltage shift in the C-V, and agreed well with the shift probed by the EFISHG. Results suggested trapped electrons were accumulated in the PI layer.
Katsuma ONO Kenya JIN'NO Toshimichi SAITO
This letter studies application of the growing PSO to the design of DC-AC inverters. In this application, each particle corresponds to a set of circuit parameters and moves to solve a multi-objective problem of the total harmonic distortion and desired average power. The problem is described by the hybrid fitness consisting of analog objective function, criterion and digital logic. The PSO has growing structure and dynamic acceleration parameters. Performing basic numerical experiments, we have confirmed the algorithm efficiency.
Yoshiro KONDO Hirofumi TANABE Tomiaki OTAKE
Electrochromic (EC) type e-paper is attracted with colorfulness and clearness. We have been researching and developing the material for EC type e-paper. We developed novel EC Polymers for e-paper. Our EC polymers are kinds of conductive polymers (CP). CP has some characteristics. One is electrochromism, and the other is electrochemical polymerization. Electrochromism of CP has a good memory effect. And electrochemical polymerization is suitable for printable electronics, for instance, ink-jet, screen print, and so on. Our EC polymers are comprised with thiophene derivatives and pi-conjugated X unit. To our knowledge, this thiophene derivatives are novel structure for EC polymers. These EC polymers have the electrochromic characteristic which change from coloration state to clear state. And we can adjust the color which we want by changing only X unit. And we made segment matrix EC display with our EC polymers by ink-jet printing. Our EC polymers are suitable for printable electronics, flexible substrate, and roll-to-roll process. We introduce our developing technologies.
Hiroyuki NAKAMURA Toshimichi SAITO
This paper presents a novel parallel boost converter using switched capacitors The switches are controlled not only by periodic clock but also by voltage-mode threshold that is a key to realize strong stability, fast transient and variable output. The dynamics is described by a piecewise linear equation, the mapping procedure is applicable and the system operation can be analyzed precisely.
Wang RONGJIE Zhan YIJU Chen MEIQIAN Zhou HAIFENG Guo KEWEI
A method of fault diagnosis was proposed for power electronics circuits based on S transforms similarity. At first, the standard module time-frequency matrixes of S transforms for all fault signals were constructed, then the similarity of fault signals' module time-frequency matrixes to standard module time-frequency matrixes were calculated, and according to the principle of maximum similarity, the faults were diagnosed. The simulation result of fault diagnosis of a thyristor in a three-phase full-bridge controlled rectifier shows that the method can accurately diagnose faults and locate the fault element for power electronics circuits, and it has excellent performance for noise robustness and calculation complexity, thus it also has good practical engineering value in the solution to the fault problems for power electronics circuits.
Masakazu MURAGUCHI Yukihiro TAKADA Shintaro NOMURA Tetsuo ENDOH Kenji SHIRAISHI
We have revealed that the electronic states in the electrodes give a significant influence to the electron transport in nano-electronic devices. We have theoretically investigated the time-evolution of electron transport from a two-dimensional electron gas (2DEG) to a quantum dot (QD), where 2DEG represents the electrode in the nano-electronic devices. We clearly showed that the coherent electron transport is remarkably modified depending on the initial electronic state in the 2DEG. The electron transport from the 2DEG to the QD is strongly enhanced, when the initial state of the electron in the 2DEG is localized below the QD. We have proposed that controlling the electronic state in the electrodes could realize a new concept device function without modifying the electrode structures; that achieves a new controllable state in future nano-electronic devices.
Toshihiro ITOH Kimikazu SANO Hiroyuki FUKUYAMA Koichi MURATA
We experimentally studied the polarization mode dispersion (PMD) tolerance of an feed-forward equalizer (FFE) electronic dispersion compensation (EDC) IC in the absence of adaptive control, in 43-Gbit/s RZ-DQPSK transmission. Using a 3-tap FFE IC composed of InP HBTs, differential group delay (DGD) tolerance at a 2-dB Q penalty is shown to be extended from 25 ps to up to 29 ps. When a polarization scrambler is used, the tolerance is further extended to 31 ps. This value is close to the tolerance obtained with adaptive control, without a polarization scrambler.
Superconducting Quantum Interference Devices (SQUIDs) are known to be the most sensitive magnetometers, used in a wide range of applications like biomagnetism, geomagnetism, Non Destructive Evaluation (NDE), metrology or fundamental science. For all these applications, the SQUID sensor is used in analog mode and associated with a carefully designed room-temperature control and/or feedback electronics. Nevertheless, the use of SQUID sensors in digital mode is of high interest for several applications due to their quantum accuracy associated to high linearity, and their potentially very high slew rate and dynamic range. The concept and performances of a low-Tc digital magnetometer based on Single-Flux-Quantum (SFQ) logic, fabricated at the FLUXONICS Foundry located at IPHT Jena, Germany, are given after a presentation of the context of development of superconductive digital magnetometers. The sensitivity, limited to one magnetic single flux quantum, and a dynamic range of 76 dB, that corresponds to an upper limit of the magnetic field amplitude higher than 5 µT, have been measured along with overnight stability. The dynamic range of about 2800 magnetic flux quanta Φ0 has been experimentally observed with an external magnetic field. First signatures of magnetic fields have been observed simultaneously with the ones of analog SQUIDs in the low noise environment of the Laboratoire Souterrain a Bas Bruit (LSBB) located in Rustrel, Provence, France.
Min LIANG Jian CHEN Lin KANG Biaobing JIN Weiwei XU Peiheng WU
Low noise terahertz (THz) receivers based on superconducting niobium nitride (NbN) hot electron bolometer (HEB) mixers have been designed, fabricated and measured for applications in astronomy and cosmology. The NbN HEB mixer consists of a planar antenna and an NbN bridge connecting across the antenna's inner terminals on a high-resistivity Si substrate. To eliminate the influence of direct detection and instability of the local oscillation (LO) power, a wire grid has been used to change the input LO power for compensating the shift of bias current during Y-factor measurement. The double sideband (DSB) receiver noise temperatures at 4.2 K without corrections have been measured from 0.65 to 3.1 THz. The excess quantum noise factor β of about 4 has been obtained, which agrees well with the calculated value. Allan variance of the HEB has been characterized, and Allan time TA longer than 0.4 s is obtained. We also estimated the temperature resolution of the HEB from the Allan variance and obtained the minimum temperature resolution of 1.1 K using a Gunn oscillator with its multipliers at 0.65 THz as an LO source.
This paper investigates the autonomous decision-making process of the selection of alternative countermeasures against threats in electronic warfare settings. We introduce a threat model, which represents a specific threat pattern, and a methodology that decides the best countermeasure against real-time threats using the decision theory. To determine the optimal countermeasure, we model the probabilities of the effects of countermeasures, if executed, and combine the probabilities with their utilities. This methodology based upon the inductive threat model calculates the expected utilities of countermeasures which are applicable given a situation, and provide an intelligent command and control agent with the best countermeasure to threats. We present empirical results that demonstrate the agent's capabilities of choosing countermeasures to threats in simulated electronic warfare settings.
Naoki KISHI Toshiki SUGAI Hisanori SHINOHARA
The synthesis of single- and double-wall carbon nanotubes by gas flow-modified, catalyst-supported chemical vapor deposition (CCVD) is reported. We have investigated the gas flow condition dependence on the synthesis of carbon nanotubes (CNTs) by placing blocks in the CCVD reactor. Carbon nanotubes having large diameters are preferentially grown under turbulent flow conditions. This indicates that the diameter distribution of CNTs can be controlled by modification of the gas flow condition in the CCVD.
Aruna P. PRIYA Preferencial C. KALA John D. THIRUVADIGAL
The idea of using molecules and molecular structures as functional electronic device, promises to substantially decrease the size and improve the performance of electronic devices. In this paper, nonequilibrium Green's function formalism (NEGF) combined with extended Huckel theory (EHT), a semiempirical approach is used to study the electron transport phenomenon in single molecular junction systems. Benzene diamine molecule is studied to investigate the bonding of amine group to gold electrodes and the electron transport across the junction. The results are compared with that of benzene dithiol molecule with thiol end groups. Furthermore, the influence of charging and torsion angle on the transport characteristics is emphasized.
Fumihiko HIROSE Yasuo KIMURA Michio NIWANO
Electrical characteristics of P3HT/Aluminum organic/ inorganic heterojunction diodes were investigated V-I and capacitance-voltage (C-V) measurements. The V-I measurement exhibited current rectification inherent in the Schottky diode, suggesting their availabilities as rectification diodes in organic flexible circuits. C-V analysis indicated the fact that the depletion layer was generated in the P3HT film in the reversed bias condition. The flat band voltage analysis suggested that the interfacial charge affected the built-in potential of the diodes. Al/P3HT heterojunction is possible to be used as not only the rectification diodes but also gate junctions for junction type field effect or static induction transistors.
Mohd Zamri Bin Mohd YUSOP Pradip GHOSH Zhipeng WANG Masaki TANEMURA Yasuhiko HAYASHI Tetsuo SOGA
Carbon nanofibers (CNFs) were fabricated on graphite plates using "Ar+ ion sputtering method" in large amount at room temperature. The morphology of CNFs was controlled by a simultaneous carbon supply during ion sputtering. CNF-tipped cones were formed on graphite plate surfaces without carbon supply whereas those with a simultaneous carbon supply featured mainly needle-like protrusions of large size. The field electron emission (FE) properties, measured using parallel plate configurations in 10-4 Pa range, showed the threshold fields of 4.4 and 5.2 V/µm with a current density of 1 µA/cm2 for CNF-tipped cones and needle-like protrusion, respectively. Reliability test results indicated that CNF-tipped cones were more stable than needle-like protrusion. The morphological change after reliability test showed a so-called "self-regenerative" process and structure damage for CNF-tipped cones and needle-like protrusions, respectively.
A prototype of a novel mobile viewer system consisting of a mobile phone and a 13.1-inch 4096-color electronic paper display has been developed. The basic concept of the system, the technological study for realizing the concept, and the specifications of the prototype are described. Possible applications of the system are also proposed.
This paper describes the architecture of an integrated platform developed for improving the development efficiency of system LSIs built into digital consumer electronics equipment such as flat-panel TVs and optical disc recorders. The reason for developing an integrated platform is to improve the development efficiency of system LSIs that serve the principal functions of the said equipment. The key is to build a common interface between each software layer, with the system LSI located at the lowest layer. To make this possible, the hardware architecture of the system LSI is divided into five blocks according to its main functionality. In addition, a middleware layer is placed over the operating system to improve the ease of porting old applications and developing new applications in the higher layer. Based on this platform, a system LSI called UniPhierTM has been developed and used in 156 product families of digital consumer electronics equipment (as of December 2008).
Sang Hyuk PARK Sangwoo KANG Seongjae CHO Dong-Seup LEE Jung Han LEE Hong-Seon YANG Kwon-Chil KANG Joung-Eob LEE Jong Duk LEE Byung-Gook PARK
A Recessed-Channel Dual-Gate Single Electron Transistor (RCDG-SET) which has the possibility of room temperature operation is proposed. Side gates of a RCDG-SET form electrical tunneling barriers around a recessed channel, which is newly introduced. Not only gate but also a recessed channel is self aligned to source and drain. Characteristics of a RCDG-SET are compared with those of previous DG-SETs through device simulation (SILVACO). Due to a recessed channel and a self aligned structure, MOSFET current which causes low Peak-to-Valley Current Ratio (PVCR) is suppressed. This property of a RCDG-SET is expected to contribute for room temperature operation.
Keiichi TANAKA Akikazu ODAWARA Atsushi NAGATA Yukari BABA Satoshi NAKAYAMA Shigenori AIDA Toshimitsu MOROOKA Yoshikazu HOMMA Izumi NAKAI Kazuo CHINONE
The Transition Edge Sensor (TES)-Energy Dispersive Spectrometer (EDS) is an X-ray detector with high-energy resolution (12.8 eV). The TES can be mounted to a scanning electron microscope (SEM). The TES-EDS is based on a cryogen-free dilution refrigerator. The high-energy resolution enables analysis of the distribution of various elements in samples under low acceleration voltage (typically under 5 keV) by using K-lines of light elements and M lines of heavy elements. For example, the energy of the arsenic L line differs from the magnesium K line by 28 eV. When used to analyze the spore of the Pteris vittata L plant, the TES-EDS clearly reveals a different distribution of As and Mg in the micro region of the plant. The TES-EDS with SEM yields detailed information about the distribution of multi-elements in a sample.
Dirk BORSTLAP Jurgen SCHUBERT Willi ZANDER Andreas OFFENHAUSSER Sven INGEBRANDT
In many different bioelectronic applications silicon field-effect devices such as transistors or nanowires are used. Usually native or thermally grown silicon oxides serve as interfacing layer to the liquid. For an effective voltage to current conversion of the devices, the main demands for interface layers are low leakage current, low defect density, and high input capacitance. In this article we describe the fabrication and characterization of ultra-thin silicon oxide/high-κ material stacks for bioelectronics. A combination of ultra-thin silicon oxide and DyScO3 revealed the best results. This material stack is particularly interesting for future fabrication of field-effect devices for bioelectronic applications.