Search

We summarize the results of precision measurement campaigns on semiconductor tunable-barrier electron pumps undertaken at NPL, over the last 5 years. We have investigated pumps of 3 different designs, fabricated in GaAs and silicon and operated on the 1-electron plateau at frequencies from 230 MHz to 1 GHz. For all measurements we find the pump current equal to e×f within the ≈1 ppm standard uncertainty of the current measurement. This accumulated data strongly suggests that accurate quantized operation of the tunable-barrier pump is a universal property, insensitive to the detailed design of the device. The data includes previously unpublished results.

We demonstrate the scaling of the current from a tunable-barrier electron pump using a cryogenic current comparator (CCC) with a turns ratio of 1:22592. The amplified current flows in a calibrated 100 kΩ resistor, and the voltage drop across this resistor is directly compared against a binary Josephson array. The experimental setup constitutes a prototype realization of the metrology triangle proposed more than 15 years ago.

Single electron transistors (SETs) have attracted attention not only to the transistor function but also their interesting characteristics. We reported that the negative conductance appeared in Coulomb diamond characteristics of silicon based SETs made by pattern dependent oxidation. This is attributable to the excited states in the quantum dot. However, it is necessary to consider the effect of electrostatic energy level in electron reservoir such as source and drain electrodes because the portion of the electrodes near the quantum dot is similar with the dot in size. In this study, we fabricated two SETs with a different structure, and investigated the influence of the energy level in small source and drain electrodes on the negative conductance.

Based on sequences of two cosmid clones from Japanese quail (Coturnix japonica, Coja), we confirmed that the syntenic cluster, GNB2L1∼BTN1∼BTN2, is located in the quail TRIM subregion of the quail major histocompatibility complex (MHC Coja) region. These cosmids also included four CjBG loci and one CjLEC locus; therefore, the quail TRIM subregion was thought to be adjacent to the BG/LEC subregion. We then identified three polymorphic markers - CjHEP21, CjTRIM39.2 and CjBTN2 - in the TRIM subregion that may be useful for the functional analysis of the MHC-Coja region. We examined MHC-Coja sequences from 321 individual quails sampled from 11 inbred strains, and we found eight alleles for each of the three genes - CjHEP21, CjTRIM39.2 and CjBTN2. These polymorphisms represent the first avian DNA markers in the TRIM subregion. Additionally, we discovered a quail-specific VNTR (variable number of long tandem repeats, 133-137 bp) in intron 7 of CjBTN2. We identified 25 haplotypes in the sample of 321 quail; these haplotypes comprised combinations of all 24 alleles of the three polymorphic genes. We suggest that there are two recombination hotspots, one between each pair of adjacent loci. All strains, except AMRP, contained multiple haplotypes; the AMRP strain contained a single, apparently fixed haplotype.

Many electrical applications of quantum dots rely on capacitively coupled gates; therefore, to make reliable devices we need those gate capacitances to be predictable and reproducible. We demonstrate in silicon nanowire quantum dots that gate capacitances are reproducible to within 10% for nominally identical devices. We demonstrate the experimentally that gate capacitances scale with device dimensions. We also demonstrate that a capacitance simulator can be used to predict measured gate capacitances to within 20%. A simple parallel plate capacitor model can be used to predict how the capacitances change with device dimensions; however, the parallel plate capacitor model fails for the smallest devices because the capacitances are dominated by fringing fields. We show how the capacitances due to fringing fields can be quickly estimated., Comment: 4 pages, 3 figures, to be published in IEEE Trans. Nano

We reported previously that ATP2B1 was one of the genes for hypertension receptivity in a large-scale Japanese population, which has been replicated recently in Europeans and Koreans. ATP2B1 encodes the plasma membrane calcium ATPase isoform 1, which plays a critical role in intracellular calcium homeostasis. In addition, it is suggested that ATP2B1 plays a major role in vascular smooth muscle contraction. Because the ATP2B1 knockout (KO) mouse is embryo-lethal, we generated mice with vascular smooth muscle cell-specific KO of ATP2B1 using the Cre-loxP system to clarify the relationship between ATP2B1 and hypertension. The KO mice expressed significantly lower levels of ATP2B1 mRNA and protein in the aorta compared with control mice. KO mice showed significantly higher systolic blood pressure as measured by tail-cuff method and radiotelemetric method. Similar to ATP2B1, the expression of the Na + -Ca 2+ exchanger isoform 1 mRNA was decreased in vascular smooth muscle cells of KO mice. However, ATP2B4 expression was increased in KO mice. The cultured vascular smooth muscle cells of KO mice showed increased intracellular calcium concentration not only in basal condition but also in phenylephrine-stimulated condition. Furthermore, phenylephrine-induced vasoconstriction was significantly increased in vascular rings of the femoral artery of KO mice. These results suggest that ATP2B1 plays important roles in the regulation of blood pressure through alteration of calcium handling and vasoconstriction in vascular smooth muscle cells.

Average position of electrons along thickness direction in a Coulomb island in an n-channel Si single-electron transistor is estimated by analyzing the back-gate voltage dependence of peak voltage (defined as the gate voltage giving a drain current peak) as a function of peak number. It is found that the accuracy of estimated average position is better than 0.5 nm and that the average position fluctuates as the peak number increases.

A diode made of a self-assembly monolayer with ferrocenyl termini shows an on/off ratio of ∼105.

Magnetic properties of manganese (Mn) nanosilicide embedded in thin silicon-on-insulator (SOI) layers are investigated. Mn nanosilicide formed by Mn+ ion implantation into a thin SOI layer followed by a thermal annealing at 600–900 °C shows soft ferromagnetism or superparamagnetism at 5 K. A monotonic decrease of the saturation magnetization is observed with increasing temperature for post implantation annealing and consequently with increasing mean particle size of nanosilicide. In addition, the magnetization is found to be enhanced when the Si surrounding the Mn nanosilicide is selectively removed. These results indicate that the magnetic moment indeed arises from the nanosilicide and is sensitive to the interface conditions.

The deep structure and evolution of the crust and upper mantle in the Pan-African terrain of the Lutzow-Holm Complex (LHC), Dronning Maud Land, East Antarctica were investigated using Deep Seismic Surveys (DSS). The DSS were conducted on the continental ice sheet of the LHC in the austral summers of 2000 and 2002 by the Structure and Evolution of the East Antarctic Lithosphere (SEAL) program. Processing of the DSS has produced enhanced reflection images of the crust–mantle boundary and of the internal crustal structure. Laminated layering around the crust–mantle boundary is well imaged using coherency enhancement processing after NMO corrections applied to far offset data. The repetitive crust–mantle transition zone imaged by the SEAL-2002 profile suggests the presence of compression stress in a NE–SW orientation during the Pan-African, which occurred during the last stage of formation of a broad mobile belt between the East and West Gondwana super-terrains. Successive break-up processes of the super-continent in mid-Mesozoic could account for the formation of the stretched reflection structure above the Moho discontinuity beneath the LHC as imaged on in the SEAL-2000 profile.

Dialysis-related amyloidosis (DRA) is one of the major complications often seen in long-term dialysis patients, and is one of the factors that decreases quality of life. β2-microglobulin (β2-m) is considered to be a major pathogenic factor in dialysis-related amyloidosis. The Lixelle adsorbent column, with various capacities, has been developed to adsorb β2-m from the circulating blood of patients with dialysis-related amyloidosis. Using a minimum type of β2-m-adsorbing column (Lixelle S-15), we evaluated its therapeutic efficacy and safety in dialysis patients. Seventeen hemodialysis patients with DRA were treated with the S-15 column for one year. Treatment was performed three times a week in this study. During the study period, pinch strength, visual analog scale for joint pain, and activities of daily living were evaluated every three months, and blood sampling was performed every six months. After one year's treatment with the S-15 column, the β2-m level decreased from 29.3±9.6mg/L to 24.7±5.1mg/L (P

Small single-electron devices (SEDs) consisting of many Si nanodots are fabricated on a silicon-on-insulator (SOI) wafer by means of pattern-dependent oxidation (PADOX) method. We investigated SEDs from two kinds of viewpoint. One is how to fabricate the nanodots, especially coupled nanodots, which are important to achieve quantum computers and single-electron transfer devices. The other is demonstration of new applications that tolerate the size fluctuation. In order to achieve multi-coupled nanodots, we developed an easy method by applying PADOX to a specially designed Si nanowire which has small constrictions at the ends of the wire. We confirmed the double-dot formation and position of the Si nanodots in the wire by analyzing the measured electrical characteristics. To achieve high functionality together with low-power consumption and tolerance to size fluctuation, we developed nanodot array device which has many input gates and outputs terminals. The fabricated three-input and two-output nanodot device actually provide high functionality such as a half adder and a full adder.

We demonstrate the tunneling in spin-split barriers made of ferromagnetic EuO grown on Si(111) substrates by molecular beam epitaxy. For 6 nm thick EuO films with high crystal quality and atomically sharp interfaces, we find a barrier height lowering driven by the spin splitting below the Curie temperature of 35 K. We determined the splitting energy to be 0.56 ± 0.03 eV at 20 K which results in a spin polarization above 90%.

We propose a method for the observation of the electron-initiated impact ionization process in Si, which is potentially capable of detecting individual impact ionization events. This method detects holes generated by the impact ionization with single charge sensitivity. We demonstrate the method at 8 K by detecting the chain of single holes generated for a constant electron-injection current with the injection-energy threshold close to the Si bandgap energy.We propose a method for the observation of the electron-initiated impact ionization process in Si, which is potentially capable of detecting individual impact ionization events. This method detects holes generated by the impact ionization with single charge sensitivity. We demonstrate the method at 8 K by detecting the chain of single holes generated for a constant electron-injection current with the injection-energy threshold close to the Si bandgap energy.

Introduction The study aimed to clarify the difficulties concerning insertion of advanced airway devices during cardiac arrest. Method In an observational study using manikins, we examined the airway management techniques of 19 teams at the Osaka Senri medical rally. For ex-post verification, we recorded chest compression and ventilation using the Resusci® Anne Advanced Skill Trainer (Laerdal, Norway) and recorded actions of the teams using a video camera. Results Only a small proportion of teams did not adopt advanced airway management (4 teams, 21.1%). Thirteen teams selected tracheal intubation. None showed chest compression interruptions during intubation manipulation, and the median duration of chest compression interruption during confirmation of postintubation was 6.4 seconds. The median duration of ventilation interruption during intubation was 45.5 seconds. When teams were evaluated for the duration of direct laryngoscopy, that is, so-called duration of intubation, the median duration was 19 seconds, which constituted a large underestimate compared with the duration of ventilation interruption. This represents an underestimation of about 27 seconds. We considered the issues to be identified for shortening the duration of ventilation interruption. Conclusion From this study, it is clear that the strategy of Guideline 2005 that was designed to minimize chest compression interruption has permeated deeply. The recommendation that the duration of intubation manipulation should not exceed 30 seconds has had various interpretations, but it is important to focus on the duration of ventilation interruption.

The objective of the present study was to conduct the genetic characterization of nine experimental chicken lines based on multilocus microsatellite analysis. Commercial chicken lines were also analyzed in order to compare their levels of genetic uniformity with those of the experimental lines. In six experimental lines, more than 80% of genotyped loci showed fixed allele for all individuals in each line, whereas only 17.5% of genotyped loci were fixed in commercial lines, at the maximum. One of experimental lines (GSN/1) was categorized as a highly inbred line on the basis of all individuals having the same, single allele at every microsatellite locus. Genetic information obtained from the present study should be helpful for the utilization and management of experimental chicken resources.

We propose a simple method for fabricating Si single-electron transistors (SET) with coupled dots by means of a pattern-dependent-oxidation (PADOX) method. The PADOX method is known to convert a small one-dimensional Si wire formed on a silicon-on-insulator (SOI) substrate into a SET automatically. We fabricated a double-dot Si SET when we oxidized specially designed Si nanowires formed on SOI substrates. We analyzed the measured electrical characteristics by fitting the measurement and simulation results and confirmed the double-dot formation and the position of the two dots in the Si wire.

This study clarified the stratigraphy and sedimentary facies of the shallow subsurface strata of the Ohmi Basin, an inland lake basin in central Japan. Stratigraphic divisions in the basin are based on regional tephra and widely distributed humic layers. The shallow subsurface strata of the basin are divided into two units. Unit II comprises middle to upper Pleistocene terrace deposits. The overlying Unit I comprises uppermost Pleistocene to Holocene postglacial deposits. Although the lithofacies of Unit II vary horizontally and vertically, the uppermost part consistently consists of humic soils containing Aira-Tn tephra (AT). This distinctive tephra is widely distributed throughout the Japanese islands. Humic soils were deposited at ca. 16.5 to 25 ka according to 14C dating. Unit I, which conformably overlies Unit II, and is mainly a repetitive succession of sand, mud, and gravel. Each layer is discontinuous in terrestrial areas, where distribution patterns of lithofacies are controlled by topography. The depth distribution of AT reflects tectonic subsidence induced by reverse faulting in the Biwako-Seigan active fault zone on the western side of Lake Biwa. Thus, tectonic movement was an important factor during sedimentation. Periodic small-scale subsidence (less than several meters per event) due to slips along faults of the Biwako-Seigan system caused discontinuities in late Quaternary fluvial deposits.

A multi-purpose seismic experiment named the 2002 integrated seismic experiment Southwest Japan was conducted in 2002 along a more-than-240-km-long line across southwest Japan from the Pacific coast to the Japan Sea coast. Its profile provides the first crustal-scale cross section across the Japanese island arc, which highlights a number of significant points related to the structural development of the arc. Major outstanding points are that the Japanese island arc is composed of two completely different crusts juxtaposed by the Median Tectonic Line (MTL), and that the MTL started its activity associated with lower crustal thinning and formation of an upper crustal-scale half-graben in Late Cretaceous.

We have developed a flexible-logic-gate single-electron device (SED) with an array of nanodots. Although the small size of SEDs is highly advantageous, the size of the nanodots inevitably fluctuates, which causes variations in device characteristics. This variability can be eliminated and high device functionality can be obtained by exploiting the oscillatory characteristics and multigate capability of SEDs. We fabricated, on a silicon-on-insulator wafer, a Si nanodot array device with two input gates and a control gate and investigated its basic operation characteristics experimentally. The device was demonstrated to operate as a logic gate providing six important logic functions ( and, or, nand, nor, xor, and xnor), which are obtained by adjusting the control-gate voltage.

In previous studies, two types of offspring were generated from germline chimera between NH-413 strain (donor) and White Leghorn L-M strain (recipient). Phenotype and symptom of type-I offspring were quite similar to that of the NH-413 strain. In the other offspring of type-II, feather color showed mixture of white and brown and the symptom was not dominantly indicated. In the present studies, sexually matured males and females of the type-l were mated each other. Form these mating. chickens manifesting completely same phenotype to that of the donor NH-413 strain; brown feather color and symptoms of Muscular dystrophy. were regenerated. Therefore, complete regeneration of the muscular dystrophy chickens Could be achieved by mating males and female offspring derived from the germline chimeras. Fertility, hatchability and Survival rate of these regenerated offspring were significantly improved as compared to that of the original NH-413 strain. The established strategies should be one of the useful systems to regenerate chickens with muscular dystrophy., Article, JOURNAL OF POULTRY SCIENCE. 46(2): 123-126(2009)

A highly functional Si nanodot array device that operates by means of single-electron effects was experimentally demonstrated. The device features many input gates, and many outputs can be attached. A nanodot array device with three input gates and two output terminals was fabricated on a silicon-on-insulator wafer using conventional Si MOS processes. Its feasibility was demonstrated by its operation as both a half adder and a full adder when the operation voltage was carefully selected.

A novel strategy has been developed to generate muscular dystrophy chickens by means of germline chimeras. Donor embryos were obtained from the New Hampshire chicken; NH-413 strain which have genes responsible for Fukuyama type muscular dystrophy (Saito et al., 2005). Donor cells were isolated from the center of area pellucida of the blastoderms. Recipient embryos were obtained from White Leghorn chicken; Line-M. The generated chimeric chickens had the donor derived brown plumage in the down in some extent, suggesting that the cells containing muscular dystrophy were introduced into the chimeras. These chimeric chickens have been raised until sexual maturity. The chimeric chickens were back-crossed to donor strain; the NH-413 strain. The phenotype of some of the offspring was very similar to that of the donor strain. The offspring showed some characters typical to the muscular dystrophy. It was suggested that the donor derived NH-413 strain offspring was generated. The established system should be one of the powerful strategies for breeding and regeneration of the muscular dystrophy chickens., Article, JOURNAL OF POULTRY SCIENCE. 46(1): 46-51(2009)

The WW domain containing E3 ubiquitin protein ligase 1 (WWP1) is classified into one of ubiquitin ligases which play an important role in ubiquitin-proteasome pathway. Previously, we identified the WWP1 gene as a candidate gene of chicken muscular dystrophy by linkage analysis and sequence comparison. However, the mechanism causing pathological changes and underlaying gene function remains elucidated. In the present study, we analyzed the WWP1 gene expression in various muscles and tissues of normal chickens, and compared with those from muscular dystrophic chickens. Two mRNA isoforms were detected in all tissues examined and revealed almost equal expression level. The WWP1 expression of dystrophic chickens was decreased in almost all skeletal muscles including unaffected muscles. These data indicate that there might not be a causal relationship between the alteration of WWP1 expression level and the severity of muscular dystrophy.

Histocompatibility was assessed in the RIR-Y8/NU, BL-E, YL, and WL-G chicken closed colonies by hemagglutination test using anti-red blood cell (RBC) antibodies (HT), skin transplantation test (STT), and formation of isohemagglutinins (FIHs) during STT. The YL individuals all showed the survival of skingrafts for more than 17 days with no FIHs in STT and no RBC antigenic variations in HT, indicating a histocompatible nature together with high homogeneity at serological loci. The BL-E as well as WL-G closed colonies were also found to be histocompatible in the STT with no FIHs, although the HT showed heterogeneities at serological locus/loci other than the B and C blood group loci which have significant effects on histocompatibility or FIHs in chicken. In the RIR-Y8/NU closed colonies, one individual in 6 reciprocal combinations of the STT showed early skingraft rejection with positive FIHs caused by different B locus alleles, and the HT suggested relatively high heterogeneities at the other serological loci too. The closed colonies of YL, BL-E, and WL-G will be useful avian materials for transplantation or related experiments, but RIR-Y8/NU needs further pedigree selection for serological homogeneity.

An electrometer based on field-effect transistors (FETs) was fabricated on a silicon-on-insulator substrate (SOI). The electrometer has a nanometer-scale small channel and a capacitively coupled node, where single electrons are stored. We discuss the dependence of the charge sensitivity of the electrometer on its structure and on its operation condition and gives guides for achieving the higher charge sensitivity. The device optimization based on this dependence allows the demonstration of the electrometer with extremely high charge sensitivity, 0.0013 e/√Hz at 1 Hz, at room temperature.

We fabricated a nanodot-array device with multiple input gates on a silicon-on-insulator (SOI) wafer by using a pattern-dependent oxidation method with multiple input gates, which embodies a new concept of a flexible single-electron device. Although the device can generate many logic functions owing to the capacitive coupling between dots and many gates, the complicated structural configuration makes it difficult to confirm the formation of the nanodot array. For further investigation of this kind of device to achieve higher functionality, it is important to demonstrate experimentally that the dot array is actually formed. We analyzed the oscillation-peak shift caused by the gate voltage change, and successfully determined the location of the dots that contributed to the experimentally observed oscillations.

Summary Aim To examine the current status and problems of resuscitation management in Japan as demonstrated at the 2006 and 2007 Osaka Senri medical rallies. Methods Using manikins, the quality of resuscitation was evaluated in 33 teams that participated in the medical rallies. The challenge was to deliver defibrillation shocks for ventricular fibrillation; data were recorded using the Laerdal PC Skill Reporting System (Norway). The teams were first subjectively (visually) evaluated by a panel of judges and these evaluations were later reaffirmed using video records. Results A ∼30 s delay was observed between the time of contact and initiation of chest compression in the teams that adopted the American Heart Association (AHA) method compared with those that adopted the European Resuscitation Council (ERC) method. Although the overall quality of chest compressions was very good, in several instances, the hand positions were inappropriate and complete chest recoil was not achieved. The left paddle was incorrectly positioned by all teams. Only 15.8% of the teams were able to deliver shocks with less than 10 s of interruption between the chest compressions. Regarding interruption of chest compressions at confirmation of correct tracheal tube placement, among the eight teams that adopted the AHA method, pauses of more than 10 s were confirmed in five (62.5%). Conclusions Significant differences in performance between the AHA and ERC methods were observed. The ERC guidelines were more rational and suitable in terms of actual application than the AHA guidelines.

We investigate the hole transport in p-channel field-effect transistors doped with boron, at low temperatures (6–28 K). In transistors with a relatively large dimension, we observe the acceptor-mediated hopping and carrier freezeout, both of which are strongly influenced by the gate bias. In nanoscale transistors, these features turn into single-charge tunneling, i.e., the trapping/detrapping of single holes by/from individual acceptors. The statistics of the appearance of the modulation in a few ten samples indicates that the number of acceptors is small, or even just one, indicating that what we have observed is single-charge-transistor operation by a single-acceptor quantum dot.

The annealing-temperature (700–900 °C) dependence of the ferromagnetism of manganese-implanted silicon is investigated. In the annealed samples, the manganese-containing nanoparticles, whose mean size was found to get bigger with temperature, are formed and these samples show ferromagnetism. We obtain evidence that the samples annealed at 800–850 °C produce two kinds of ferromagnets and that one of them offers a coercivity as high as 2500 Oe, suggesting the possibility of Si-based nanostructures with stable ferromagnetism. The origin of these ferromagnetisms is also discussed in conjunction with the size distribution of the nanoparticles.

The single-electron device (SED) enables the control of electron motion on the level of an elementary charge. Single-charge transfer devices are special SEDs that enable single-electron transfer synchronized with the gate clock. They have the potential for extremely low transfer error rates and are expected to be building blocks for future information processing and electrical metrology. We have been pursuing the fabrication of Si-based SEDs using CMOS technology with the help of electron-beam lithography and have recently demonstrated the single-charge transfer devices. The devices are composed of one Si quantum dot sandwitched between two tiny MOS gates and can operate at much higher temperatures than those of former metal-based and compound-semiconductor-based devices. This opens up the possibility of the practical use of clocked single-charge transfer.

A simple measurement method is proposed for extracting capacitances in nanometer-scale metal-oxide-semiconductor field-effect transistors (MOSFETs). The method utilizes two serially connected MOSFETs and an optional metal layer above the intermediate node between MOSFETs. Gate-drain overlap capacitance and capacitances around the intermediate node, including one related to the metal layer, can be obtained by measuring the transfer current when two MOSFETs are alternately turned on at high frequency. High sensitivity in the order of attofarad is demonstrated using silicon-on-insulator (SOI) MOSFETs with gate length of 140∼300 nm and channel width of 320 nm. The proposed method is useful not only in optimizing the high-frequency performance of the scale-down devices, but also in estimating the instability (i.e. kT/C noise) and single-electron charging effect in nanometer-scale circuits.

著者人数：14名, Accepted: 2007-04-11, 資料番号: SA1000121000

Hayabusa performed five descents last November, among which two touching-down flights were included. Actually Hayabusa made three touching-downs and one long landing on the surface of Itokawa during those two flights. This paper summarizes how series of descents were planned and operated. The contents focus their attention on the correction maneuvers planning as well as what kind of terminals with what kind of software tools were actually built and used. The project team had distilled and accumulated their experiences through the rehearsal flights and accomplished this difficult mission. This paper presents the entire story about it.

Muscular dystrophies, a group of inherited diseases with the progressive weakness and degeneration of skeletal muscle, contain genetically variable diseases. Though chicken muscular dystrophy with abnormal muscle (AM) has long been known, the gene responsible has not yet been identified. In this study, a resource family for AM was established with 487 F2 individuals and 22 gene markers, including microsatellite and insertion–deletion markers, were developed. The haplotypes were analyzed with these markers for the candidate region of GGA2q described in a previous study. The candidate region was successfully narrowed down to approximately 1Mbp. The region included seven functional genes predicted as the most likely AM candidates.

A single-electron turnstile and electrometer circuit was fabricated on a silicon-on-insulator substrate. The turnstile, which is operated by opening and closing two metal-oxide-semiconductor field-effect transistors (MOSFETs) alternately, allows current quantization at 20 K due to single-electron transfer. Another MOSFET is placed at the drain side of the turnstile to form an electron storage island. Therefore, one-by-one electron entrance into the storage island from the turnstile can be detected as an abrupt change in the current of the electrometer, which is placed near the storage island and electrically coupled to it. The correspondence between the quantized current and the single-electron counting was confirmed.

Accepted: 2006-05-09, 資料番号: SA1000603000

A polyalkylated triamine, 2,2′,4,4′-tetrabromo-4″-methyl-5,5′-bis(di(3,4-di-methylphenyl)amino)triphenylamine, was designed and successfully synthesized as a model precursor for purely organic cationic high-spin systems. Cyclic voltammetry measurement revealed that the triamine gives stable mono- and dicationic states and fairly unstable tricationic state. Novel electron transfer stopped-flow (ETSF) methods were invoked for characterizing the absorption spectra of the corresponding mono- and oligo-cationic states. The triplet state of the dication was confirmed by ESR spectroscopy.

Flicker or 1/f noise in metal-oxide-semiconductor field-effect transistors (MOSFETs) has been identified as the main source of noise at low frequency. It often originates from an ensemble of a huge number of charges becoming trapped and de-trapped, or from mobility fluctuation. However, for nanoscale transistors, equations based on the density of traps are no more valid due to the small number of traps. Fluctuations at contacts can also be the dominant source of noise. Here, we summarize our results in this topic and show in addition that nanoscale transistors provide unique opportunities for metrological studies of noise. In particular, we propose an alternative to the criticized but widely used unified number and correlated mobility fluctuation model for MOSFETs, discuss the dielectric polarization/mobility noises as sources of 1/f noise for trap-free gate oxides and a model for Schottky-barrier-based nanoscale transistors. In a second part, we summarize our results for noise in liquid-gated nanoscale (0D) transistor sensors with applications in energy harvesting and biosensing.

Valleytronics is rapidly emerging as an exciting area of basic and applied research. In two-dimensional systems, valley polarization can dramatically modify physical properties through electron–electron interactions as demonstrated by such phenomena as the fractional quantum Hall effect and the metal-insulator transition. Here, we address the electrons' spin alignment in a magnetic field in silicon-on-insulator quantum wells under valley polarization. In stark contrast to expectations from a non-interacting model, we show experimentally that less magnetic field can be required to fully spin polarize a valley-polarized system than a valley-degenerate one. Furthermore, we show that these observations are quantitatively described by parameter-free ab initio quantum Monte Carlo simulations. We interpret the results as a manifestation of the greater stability of the spin- and valley-degenerate system against ferromagnetic instability and Wigner crystalization, which in turn suggests the existence of a new strongly correlated electron liquid at low electron densities., In the emerging field of valleytronics, the valley degree of freedom of electrons is exploited in addition to charge and spin for novel functionalities. Here, Renard et al. show how valley polarization can facilitate spin-polarization in a silicon-on-insulator quantum well.

The MUSES-C was launched on May 9th of this year and was named ‘Hayabusa’. It was aimed to be the world's first sample and return from a near Earth asteroid, 1998SF36 now renamed “Itokawa”. The spacecraft is a kind of technology demonstrator with four key technologies. The paper presents a quick report on the initial operation of the ion engines aboard and will show how the attitude control has been performed incorporating the closed loop de-saturation function on board. The paper also presents how much delta-V has been applied to the spacecraft as well as how the orbit determination under the low-thrust acceleration has been performed.

Quantum mechanical features of even the most basic of semiconductor components can be expected to become of paramount importance for future nanoelectronics and quantum information technology. Here, we show that the conductivity of even a two-dimensionally extended double-gate silicon-on-insulator metal-oxide-silicon field-effect transistor can develop a distinct peak structure in its top-gate voltage dependence at low temperatures, due to the discreteness of subband edges resulting from quantum mechanical confinement in the vertical gating direction. Our findings are confirmed using low-temperature magnetic field measurements