The real capacity of graphene and the lithium-storage process in graphite are two currently perplexing problems field lithium ion batteries. Here we demonstrate a three-dimensional bilayer foam with few defects predominant Bernal stacking configuration, systematically investigate its capacity, process, kinetics, resistances. We clarify that atoms can be stored only interlayer propose first ever planar lithium-intercalation model for graphenic carbons. Corroborated by theoretical...

Magnetoconductance (MC) at low temperature was measured to investigate spin-related transport affected by spin-orbit interaction (SOI) in III-VI compound $n$-type GaSe thin films. Results reveal that MC shows weak antilocalization (WAL). Its and gate voltage dependences the dominant spin relaxation is governed D'yakonov-Perel' mechanism associated with Rashba SOI. The estimated SOI strength much stronger than of III-V GaAs quantum wells, although energy gap split-off band closely resemble...

Continuous-wave (CW) single-frequency terahertz (THz) waves were generated using difference-frequency generation via excitation of phonon-polaritons in GaP. The two pump sources an external cavity laser diode (LD) and LD-pumped Nd : YAG laser. power density the latter beam was enhanced by a ytterbium-doped fiber amplifier. incident beams focused to near wavelength THz waves. This optical alignment enabled us generate frequency-tunable CW 0.69-2.74 range. With fixed angle between beams, we...

The double-yield peak and the site exchange of responsible interstitial atoms on annealing have been observed for first time in a low-dose As+-ion-implanted GaAs crystal by means high-depth resolution multidirectional Rutherford back-scattering (RBS)/channelling technique. newly second is located deeper than conventional around projected range Rp. After at 200-250 degrees C, it found that both peaks change their sites during aging low temperature (RT approximately 40 C) occupy more stable...

The terahertz (THz) frequency range corresponds to molecular vibrations or relaxation modes such as those for the hydrogen bond. Most biomolecules are activated only in aqueous solutions, thus, understand function and structure of biomolecules, it is necessary investigate characteristics electromagnetic waves hydrated samples. THz radiation causes little damage human body, thus expected that can be applied noninvasive examinations. However, spectrometry transmitted light difficult, since...

The photocapacitance (PHCAP) method in the constant capacitance condition has been applied to determine energy and density of deep levels within limits a certain depletion layer thickness as function photon voltage. Samples used were various n-type GaAs crystals annealed for long time under excess As vapor pressure rapidly cooled. present PHCAP investigations have revealed several stoichiometry-dependent including some photoquenching levels. These are Ec−0.66 −0.72 eV donors, level at 1.03,...

A novel non-destructive inspection method using terahertz waves for the detection of broken wires in copper cables shielded by insulating polymer opaque visible and near infrared light region is presented. Terahertz reflection imaging, a 0.14 THz IMPATT oscillator Schottky barrier detector, was applied to insulated that had been artificially damaged. The internal embedded polyethylene can be clearly visualized radiation. It shown gap wire detected decrease intensity reflected signal where...

We describe a scheme for efficient terahertz (THz) generation using cascaded optical parametric oscillator GaP sheet cavity. By choosing an appropriate pump wavelength and cavity design, the cascading process contributes to THz-wave generation, resulting in high output peak power of 1.8 MW photon conversion efficiency 1.086 at 3 THz. This exceeds Manley–Rowe limit, method described here is applicable widely tunable high-power optically isotropic nonlinear material, such as GaAs, InP, ZnTe,...

The interplanar binding strength of layered GaSe1-xTex crystals was directly measured using a tensile testing machine. were grown by low temperature liquid phase solution method under controlled Se vapor pressure. stoichiometry-controlled crystal has the ε-polytype structure GaSe, where Te atoms are substituted for some in GaSe crystal. effect adding on bonding between layers determined from direct measurements van der Waals energy. energy increased 0.023 × 106 N/m2 to 0.16 (x = 0.106).

We constructed rib waveguides from GaP material using an inductively coupled plasma reactive ion etching technique based on Ar/Cl2 gas application. obtained a waveguide with height of 200 μm. Terahertz-wave generation the GaP-crystal was demonstrated via collinear phase-matched difference-frequency mixing near-infrared light. The terahertz output peak corresponding to fundamental modes appeared around 0.75 THz for 1-mm-wide waveguide. position mode shifted 1.32 200-μm-wide waveguide, which...

テラヘルツ(THz)波は光と電波の両方の特性を併せ持つ電磁波であるため,不透明な塗膜を透過した金属表面からの反射光が検出可能である.本研究では,THz波による,目視できない塗膜下金属表面の非破壊腐食検査へ向けたイメージング測定技術の確立に取り組んだ.表面にスクラッチ痕を形成し,5%塩化ナトリウム水溶液噴霧によって腐食させた溶融亜鉛めっき鋼板を試験片として用いた.THz周波数固定イメージング測定には,GaP結晶を用いた差周波混合による周波数可変単色THz光源を用いた.2.0 THzおよび2.8 THz吸光度の大きな領域がスクラッチ痕周辺に観測された.蛍光X線(XRF)マッピング像と比較すると塗膜下金属表面に形成された腐食成分は塩化亜鉛あるいは塩基性塩化亜鉛に推定された.溶融亜鉛めっき鋼板に対するTHz分光イメージング測定およびµXRFマッピング測定より,THz波が塗膜下金属表面の非破壊腐食状態検査を行う手法として有用であることを示した.

Indium selenide compounds are promising materials for energy conversion, spintronic applications, and chemical sensing. However, it is difficult to grow stoichiometric indium crystals due the high equilibrium selenium vapor pressure complicated phase system of compounds. In this paper, we apply a novel convenient crystal growth method, in which saturated solution grown by application vapor. at higher than applied molten indium, such that continuously dissolves into until solubility...

We investigated methods for improvement of continuous-wave (CW) terahertz (THz) output power by laser diode (LD) pumping in noncollinear phase-matched difference frequency generation (DFG). The effects interaction length and beam spot size input lasers (near-IR) GaP crystals were studied. THz wave dependence on various sizes was it observed that an 4 nW obtained with a 20 mm long crystal at 1.5 THz. Also, the absorption coefficient dominant longer high frequencies (above 2.5 THz). (1.2...

Concrete is the most widely used for construction materials in world. Water content of concrete an important parameter terms durability structures. Terahertz (THz) waves, which a porous and absorbable material, have been studied order to establish new non-contact inspection technology maintenance In this study, THz transmittance reflectance drying process were measured with 60 GHz GUNN diode absorption coefficient analyzed various water contents. It shown that quantitative detection below...

Terahertz (THz) wave generation via difference frequency mixing (DFM) process in strain silicon membrane waveguides by introducing the straining layer is theoretically investigated. The Si(3)N(4) induces anisotropic compressive core and results appearance of bulk second order nonlinear susceptibility χ((2)) breaking crystal symmetry. We have proposed waveguide structures for THz under DFM .using modal birefringence core. Our simulations show that an output power up to 0.95 mW can be achieved...

In order to investigate the infrared activities of corrosion products copper in terahertz (THz) frequency band, THz absorption spectra (I) oxide (Cu 2 O) and (II) (CuO) powders are measured. view practical application for non-destructive inspection wire deterioration, reflectance conductive wires with without oxidization were also spectroscopy results have shown some clear specific bands 1-5THz region, reflection revealed intensity difference at around 1.7THz band between corroded...

The excitation photocapacitance method was applied to n-GaAs:Te (n=4×1016cm−3) prepared by annealing under various excess arsenic vapor pressures. By changing the primary photon energies, emission spectra for EL20→EL2+ and EL2+→EL2++ transitions were determined. Considering electron capture processes of valence band (VB)→EL2+ (0.67eV) VB→EL2++ (0.47eV) at 77K, Frank–Condon shifts (dFC) annealed GaAs crystals determined EL2+ level on basis configuration coordinate model. It shown that lattice...