Gapless edge states localized to odd/even layers of AA'-stacked honeycomb multilayers with staggered AB-sublattice potentials.

In honeycomb multilayers with staggered AB-sublattice potentials, we predict gapless edge states localized to either of the odd and the even layers for the AA[Formula: see text] stacking order in which the sublattice-pseudospin polarizations of adjacent layers are antiparallel. Gaps in the projected layer-pseudospin spectrum suppress interlayer hopping between odd and even layers. The layer-valley Chern number corresponding to the edge states was obtained by decomposing the occupied state into two layer-pseudospin sectors by using a projected layer-pseudospin operator.

Surface reconstruction and band bending in hydrogen-adsorbed [Formula: see text] topological insulator.

We have investigated the effects of hydrogen adsorption on the [Formula: see text] topological insulator by using the density functional theory calculations. We found that hydrogen adsorption on the surface leads to surface reconstruction to reduce the band bending effect. Contrasting to a previous report that hydrogen adsorption transforms the single Dirac cone at the Brillouin zone center into three Dirac cones at the zone boundary, the Dirac cones at the zone center corresponding to the topological surface states were confirmed to be robust against the hydrogen adsorption and surface reconstruction.

Strain-induced topological phase transition with inversion of the in-plane electric polarization in tiny-gap semiconductor SiGe monolayer.

Our density functional theory calculations show that tiny-gap semiconductor SiGe monolayer is a quantum valley Hall insulator with a spontaneous electric polarization and, under a small biaxial strain, undergoes a topological phase transition between the states with opposite valley Chern numbers. The topological phase transition entails abrupt inversion of the in-plane electric polarization corresponding to inversion of the sublattice pseudospin polarization, while the out-of-plane electric polarization shows a linear response to the biaxial strain as well as to the perpendicular electric field regardless of the phase transition. Thus, the quantum valley Hall state entails in-plane ferroelectricity corresponding to a sublattice pseudospin ferromagnetism.

Quantum valley Hall effect in wide-gap semiconductor SiC monolayer.

We have investigated the valley Chern number and gapless edge states in wide-gap semiconductor SiC and BN monolayers by using the density functional theory calculations. We found that while SiC monolayer has a non-quantized valley Chern number due to a partial mixing of the Berry curvature peaks pertaining to the opposite valleys, there exist topologically protected gapless edge states within the bulk gap, leading to a quantum valley Hall effect. Doping of the opposite charge carriers causes a backscattering-free valley current flowing on the opposite edge, which can be used for experimental confirmation and application at room temperature.

Quantum spin-valley Hall effect in AB-stacked bilayer silicene.

Our density functional theory calculations show that while AB-stacked bilayer silicene has a non-quantized spin-valley Chern number, there exist backscattering-free gapless edge states within the bulk gap, leading to a quantum spin-valley Hall effect. Using a tight-binding model for a honeycomb bilayer, we found that the interlayer potential difference and the staggered AB-sublattice potential lead to abrupt and gradual change of the valley Chern number from a quantized value to zero, respectively, while maintaining backscattering-free gapless edge states if the valley Chern number is not too close to zero. Under an inversion symmetry-breaking potential in the form of the staggered AB-sublattice potential, such as an antiferromagnetic order and a hexagonal diatomic sheet, a finite but non-quantized (spin-)valley Chern number can correspond to a quantum (spin-)valley Hall insulator.

NMR Observation of Mobile Protons in Proton-Implanted ZnO Nanorods.

The diffusion properties of H(+) in ZnO nanorods are investigated before and after 20 MeV proton beam irradiation by using (1)H nuclear magnetic resonance (NMR) spectroscopy. Herein, we unambiguously observe that the implanted protons occupy thermally unstable site of ZnO, giving rise to a narrow NMR line at 4.1 ppm.

Extreme sensitivity of the electric-field-induced band gap to the electronic topological transition in sliding bilayer graphene.

We have investigated the effect of electronic topological transition on the electric field-induced band gap in sliding bilayer graphene by using the density functional theory calculations. The electric field-induced band gap was found to be extremely sensitive to the electronic topological transition. At the electronic topological transition induced by layer sliding, four Dirac cones in the Bernal-stacked bilayer graphene reduces to two Dirac cones with equal or unequal Dirac energies depending on the sliding direction.

Layer-selective half-metallicity in bilayer graphene nanoribbons.

Half-metallicity recently predicted in the zigzag-edge graphene nanoribbons (ZGNRs) and the hydrogenated carbon nanotubes (CNTs) enables fully spin-polarized electric currents, providing a basis for carbon-based spintronics. In both carbon systems, the half-metallicity arises from the edge-localized electron states under an electric field, lowering the critical electric field Dc for the half-metallicity being an issue in recent works on ZGNRs. A properly chosen direction of the electric field alone has been predicted to significantly reduce Dc in the hydrogenated CNTs, which in this work turned out to be the case in narrow bilayer ZGNRs (biZGNRs).

An alternative method using microwave power saturate in fingernail/electron paramagnetic resonance dosimetry.

An alternative method for fingernail/electron paramagnetic resonance (EPR) dosimetry valid at low doses (0-3 Gy) is suggested in this paper. The method consisted of two steps. The first step involved dehydrating fingernail clippings to remove their water content by heating them at 70 °C for 72 h.

Field-induced transition from room-temperature ferromagnetism to diamagnetism in proton-irradiated fullerene.

Room-temperature ferromagnetism in proton-irradiated C60 fullerene is demonstrated. The ferromagnetism turns into diamagnetism intrinsic to the fullerene as the magnetic field increases above a critical field.

Half-metallic carbon nanotubes.

Half-metallicity in carbon nanotubes is achieved and controlled by hydrogen adsorption patterns. The edge states in carbon nanotubes are unstable under an electric field due to the spin-conserving electron transfer between the edges, but a large enough transfer barrier between the edge states, obtained by controlling the adsorption patterns, renders the CNTs half-metallic.

Intrinsic impurity-band Stoner ferromagnetism in C60Hn.

We identify Stoner ferromagnetism in fcc C60H(n) (n=odd) by using a local density approximation in the framework of the density functional theory. Hydrogen chemisorption on fullerenes creates quasilocalized π electrons on the fullerene surface, overlapping of their wave functions giving rise to a narrow half filled impurity band in the fcc C60H(n). The Stoner-type ferromagnetic exchange between the itinerant electrons leads to spin-split impurity bands.

RpS3 translation is repressed by interaction with its own mRNA.

Ribosomal protein S3 (RpS3) is a well-known multi-functional protein mainly involved in protein biosynthesis as a member of the small ribosomal subunit. It also plays a role in repairing various DNA damage acting as a repair UV endonuclease. Most of the rpS3 pool is located in the ribosome while the minority exists in free form in the cytoplasm.

Electron spin resonance of proton-irradiated graphite.

In the case of colossal magnetoresistance in the perovskite manganites, "double exchange" mediated by the itinerant spins is believed to play a key role in the ferromagnetism. In contrast, the conventional "Heisenberg" interaction, i.e.

Layered copper hydroxide n-alkylsulfonate salts: synthesis, characterization, and magnetic behaviors in relation to the basal spacing.

A series of hybrid inorganic-organic copper(II) hydroxy n-alkylsulfonate with a triangular lattice, Cu(2)(OH)(3)(C(n)H(2)(n)(+1)SO(3)) (n = 6, 8, 10), are prepared by anion exchange, starting from copper hydroxy nitrate Cu(2)(OH)(3)NO(3). These compounds show a layered structure as determined by X-ray diffraction, with interlayer distances of 14.3-34.

A series of long-chain lamellar hydrated copper(II) alkylsulfonates with different chain molecular assemblies.

Reaction of copper(II) salts with n-alkylsulfonate anions yields light blue lamellar Cu(C(n)H(2n + 1)SO3)2 x zH2O displaying distinct (mono/bi-layer) chain packing with increasing alkyl chain lengths. This may be attributed to the amphiphilic nature of the surfactants, i.e.

Electron paramagnetic resonance study reveals a putative iron-sulfur cluster in human rpS3 protein.

The human ribosomal protein S3 (rpS3) functions as a component of the 40S subunit and as a UV DNA repair endonuclease. This enzyme has an endonuclease activity for UV-irradiated and oxidatively damaged DNAs. DNA repair endonucleases recognize a variety of UV and oxidative base damages in DNA from E.