A5070513041- Gas Sensing Nanomaterials and Sensors
- ZnO doping and properties
- Electronic and Structural Properties of Oxides
- Microfluidic and Capillary Electrophoresis Applications
- Physics of Superconductivity and Magnetism
- Microfluidic and Bio-sensing Technologies
- Nanopore and Nanochannel Transport Studies
- Nanowire Synthesis and Applications
- Analytical Chemistry and Sensors
- Advanced biosensing and bioanalysis techniques
- Advanced Memory and Neural Computing
- Magnetic and transport properties of perovskites and related materials
- Semiconductor materials and devices
- Advanced Chemical Sensor Technologies
- Acoustic Wave Resonator Technologies
- Copper-based nanomaterials and applications
- Innovative Microfluidic and Catalytic Techniques Innovation
- Advanced Control Systems Optimization
- Anodic Oxide Films and Nanostructures
- Magnetic properties of thin films
- Advanced Condensed Matter Physics
- Molecular Junctions and Nanostructures
- Ferroelectric and Negative Capacitance Devices
- Nanofabrication and Lithography Techniques
- 3D Printing in Biomedical Research
Kyushu University
2015-2024
The University of Tokyo
2020-2024
Shimadzu (Japan)
2007-2024
Hitachi (Japan)
1999-2023
Tokyo Institute of Technology
2010-2023
Kasugai Municipal Hospital
2018-2021
Osaka University
2002-2017
Osaka Research Institute of Industrial Science and Technology
1993-2015
Keio University
2014
Japan Science and Technology Agency
2004-2008
We demonstrate the first reported methodology using nanowires that unveils massive numbers of cancer-related urinary microRNAs.
Abstract On the development of flexible electronics, a highly nonvolatile memory, which is an important circuit component for portability, necessary. However, flexibility existing memory has been limited, e.g . smallest radius into can be bent millimeters range, due to difficulty in maintaining properties while bending. Here we propose ultra resistive using Ag-decorated cellulose nanofiber paper (CNP). The CNP devices showed stable effects with 6 orders ON/OFF resistance ratio and small...
Thin films of (Ca,Sr)CuO2, the parent material high Tc cuprate superconductors, have been formed by laser ablation method under molecular beam epitaxial condition, and growth mechanism has investigated with reflection high-energy electron diffraction (RHEED). Analyses RHEED patterns intensity oscillations show that this grows two-dimensional layer growth. When all metal elements are supplied simultaneously in NO2 atmosphere, occurs unit-cell (Ca,Sr)CuO2. Furthermore, it become evident unit...
Crystallized as-grown Bi(Pb)-Sr-Ca-Cu-O thin films are formed by the laser ablation method at a substrate temperature as low 480 °C under N2O gas flow. Moreover, film, which has crystal structure consisting of four or five CuO2 layers between adjacent Bi2O2 layers, can be combination flow and successive deposition with excimer pulses.
Resistive switching (RS) memory effect in metal-oxide-metal junctions is a fascinating phenomenon toward next-generation universal nonvolatile memories. However the lack of understanding electrical nature RS has held back applications. Here we demonstrate bipolar cobalt oxides, such as conduction mechanism and location, by utilizing planar single oxide nanowire device. Experiments field devices multiprobe measurements have shown that nanoscale oxides originates from redox events near cathode...
Electrically driven resistance change in metal oxides opens up an interdisciplinary research field for next-generation non-volatile memory. Resistive switching exhibits electrical polarity dependent "bipolar-switching" and a independent "unipolar-switching", however tailoring the has been challenging issue. Here we demonstrate scaling effect on emergence of by examining resistive behaviors Pt/oxide/Pt junctions over 8 orders magnitudes areas. We show that two polarities can be categorised as...
Here we report the thermal management of oxide nanowire sensor in both spatial and time domains by utilizing unique properties nanowires, which are (1) reduced conductivity (2) short relaxation down to several microseconds. Our method utilizes a pulsed self-Joule-heating suspended SnO2 device, enables not only gigantic reduction energy consumption ∼102 pJ/s, but also enhancement sensitivity for electrical sensing NO2 (100 ppb). Furthermore, demonstrate applicability present as sensors on...
Progress toward the concept of "a trillion sensor universe" requires devices to become more abundant, ubiquitous, and be potentially disposable. Here, we report a paper-based disposable molecular device constructed from nanowire based on common zinc oxide (ZnO), wood-derived biodegradable cellulose nanofiber paper substrate, low-cost graphite electrode. The ZnO nanowire/cellulose composite structure is embedded in surface substrate via two-step papermaking process. This provides mechanically...
We have formed epitaxial LiNbO3 thin films of high quality on sapphire substrates (001) using an excimer-laser ablation technique and evaluated the surface acoustic wave (SAW) properties these films. It is demonstrated that are candidates for a frequency SAW filter because their velocities propagation (5300–6600 m/s) good temperature coefficients (−34 to −80 ppm/ °C).
Hydrothermal ZnO nanowires have shown great potential for various nanoscale device applications due to their fascinating properties and low-temperature processing. A preferential crystal growth of (0001) polar plane is essential fundamental realize the anisotropic nanowire growth. Here we demonstrate that a critical concentration nucleation strongly depends on plane, which plays an important role hydrothermal nanowires. We measure rate each when varying Zn ionic species by using regular...
Electrokinetic manipulations of biomolecules using artificial nanostructures within microchannels have proven capability for controlling the dynamics biomolecules. Because there is an inherent spatial size limitation to lithographic technology, especially with a small diameter and high aspect ratio, manipulating single biomolecule such as in DNA elongation before nanopore sequencing still troublesome. Here we show feasibility self-assembly nanowire array embedded microchannel on fused silica...
Analyzing sizes of DNA via electrophoresis using a gel has played an important role in the recent, rapid progress biology and biotechnology. Although analyzing over wide range short time is desired, no existing methods have been able to fully satisfy these two requirements. Here we propose novel method rigid 3D network structure composed solid nanowires within microchannel. This enables analysis under applied DC electric fields for large size (100 bp–166 kbp) 13 s, which are much wider...
Metal oxide nanowires hold great promise for various device applications due to their unique and robust physical properties in air and/or water also abundance on Earth. Vapor-liquid-solid (VLS) growth of metal offers the high controllability diameters spatial positions. In addition, VLS has applicability axial radial heterostructures, which are not attainable by other nanowire methods. However, material species available substantially limited even though variety species, fascinating...
We demonstrate the facile, rational synthesis of monodispersedly sized zinc oxide (ZnO) nanowires from randomly seeds by hydrothermal growth. Uniformly shaped nanowire tips constructed in ammonia-dominated alkaline conditions serve as a foundation for subsequent formation monodisperse nanowires. By precisely controlling sharp tip and nucleation, our method substantially narrows distribution ZnO diameters σ = 13.5 nm down to 1.3 controls their diameter completely bottom-up method, even...
The deposition of lithium niobate (LiNbO3) films on sapphire substrates (001) and (110) using pulsed excimer-laser ablation has been investigated. effect several experimental parameters. Li/Nb ratio the target, substrate temperature, pressure composition gas during deposition, resulting film quality are examined. Under optimized conditions, epitaxial LiNbO3 high deposited. as-grown sufficiently piezoelectric to fabricate surface acoustic wave (SAW) devices without poling. Rayleigh Love-type...
Abstract Separation and analysis of biomolecules represent crucial processes for biological biomedical engineering development; however, separation resolution speed still require improvements. To achieve in a short time, the use highly-ordered nanostructures fabricated by top-down or bottom-up approaches have been proposed. Here, we reported on three-dimensional (3D) nanowire structures embedded microchannels approach ultrafast small biomolecules, such as DNA, protein RNA molecules. The 3D...
Highly conductive and transparent indium–tin oxide (ITO) single-crystalline nanowires, formed by the vapor–liquid–solid (VLS) method, hold great promise for various nanoscale device applications. However, increasing an electrical conductivity of VLS grown ITO nanowires is still a challenging issue due to intrinsic difficulty in controlling complex material transports process. Here, we demonstrate crucial role preferential indium nucleation on using gold catalysts. In spite fact that vapor...
Measuring ionic currents passing through nano- or micropores has shown great promise for the electrical discrimination of various biomolecules, cells, bacteria, and viruses. However, conventional measurements have there is an inherent limitation to detectable particle volume (1% pore volume), which critically hinders applications real mixtures biomolecule samples with a wide size range suspended particles. Here we propose rational methodology that can detect 0.01% by measuring transient...
Abstract A crystal growth of hydrothermal ZnO nanowires essentially requires a concentration control within so-called “concentration window”, where the anisotropic preferentially occurs. Although understanding what exactly determines width window” is important to tailor process, fundamental knowledge as still scarce. Here we report effect ammonia addition on using conventional nanowire growth. We found that substantially narrows window”. Within narrow range zinc complex concentration,...
An approach to evaluate the two-dimensional nature in a high Tc superconductor is examined on superconducting superlattice prepared by stacking of and nonsuperconductor layers. The Bi2Sr2(Ca1−xYx)1Cu2O8-based superlattices have been formed two different unit cell layers containing yttrium concentrations. One layer contains lower concentration (x=0.15) be superconductor, other higher (x=0.5) semiconductor, these are periodically stacked with appropriate ratios. These exhibit same...
Oriented Bi-Sr-Ca-Cu-O thin films with their c -axis perpendicular to the substrate surface were formed by a laser sputtering method. Films are classified into three types: semiconductor, an 80 K superconductor and 120 superconductor, long axis lengths of unit cell be 24.4 Å, 30.8 Å 36.8 respectively.
Electrically driven resistance change phenomenon in metal/NiO/metal junctions, so-called resistive switching (RS), is a candidate for next-generation universal nonvolatile memories. However, the knowledge as to RS mechanisms unfortunately far from comprehensive, especially spatial location, which crucial information design reliable devices. In this communication, we demonstrate identification of location bipolar by introducing asymmetrically passivated planar NiO nanowire junctions. We have...
This study demonstrates the effect of surroundings on a memristive switching at nanoscale by utilizing an open top planar-type device. NiOx and CoOx devices have exhibited behavior under atmospheric pressure, whereas TiO2-x did not show even same surroundings. A has emerged when reducing ambient pressure and/or employing SiO2 passivation layer. These results reveal that thermodynamical interaction with critically determines occurrence via varying stability nonstoichiometry. Since this tends...