Mineo Saito

Stability of the quasicubic phase in the initial stage of the growth of bismuth films on Si(111)-7×7

We discuss the results of the scanning tunneling microscopy (STM) investigations and ab initio calculations of the structure and stability of the quasicubic Bi{012} film formed in the initial stage of the bismuth deposition on the Si(111)-7×7 surface at room temperature. Results of our STM experiments show that paired-layer Bi{012} film grows on top of the initially formed wetting layer, with the Si 7×7 lattice preserved underneath. The pairing of the layers in the {012} film leads to the substantial stabilization of the film when it consists of an even number of layers and only even-number layered Bi{012} islands are observed to be stable. The buckling of the atoms in the topmost paired layer induced by the relaxation of the film is evidenced by the high-resolution STM images.

The effect of water on infrared spectra of DNA.

The effect of water on infrared (IR) spectra of DNA is studied by using first-principles calculations based on the hybrid density functional theory. Our calculations of frequencies of C = O stretching modes in DNA without water do not reproduce the IR spectra, whereas calculations for DNA surrounded by water reproduce the IR spectra well. We also find that the energy of adsorption of one water molecule around a C = O site is large ([Formula: see text]xa0eV) owing to hydrogen bond formation. We therefore conclude that the effect of water plays an important role as regards IR spectra of DNA in a water solution.

Spin polarized positron lifetimes in ferromagnetic metals: First-principles study

We carry out spin-polarized positron lifetime calculations for ferromagnetic metals using the electron?positron density functional theory (DFT). We investigate Fe, Co, and Ni and find that the differences between the positron lifetimes for their minority and majority spins (?? ? ??) are 11.85, 3.75, and ?4.37 ps, respectively. The negative lifetime difference of Ni is presumed to originate from an unlocalized distribution of minority electrons.

Density-functional-theory-based calculations of formation energy and concentration of the silicon monovacancy

By using first-principles calculations, we study the formation energy and concentration of the silicon monovacancy. We use large-scale supercells containing up to 1728 atomic sites and confirm the convergence of calculational results with respect to the cell size. The formation energy is calculated to be 3.46 eV, and the vacancy concentration at the silicon melting point is estimated to be 7.4 × 1016 cm−3. These values are consistent with experimental results. We find that the vibrational effect significantly increases the vacancy concentration about 104 times.

Strain-controlled spin splitting in the conduction band of monolayer WS 2

Spin splitting bands that arise in the conduction band minimum (CBM) of the

Persistent spin helix on a wurtzite ZnO

{text{WS}}_{2}

(10\bar{1}0)

monolayer (ML) play an important role in the spin-orbit phenomena such as spin-valley coupled electronics. However, application of strain strongly modifies electronic properties of the

surface: First-principles density-functional study

{text{WS}}_{2}

Spin-split bands of metallic hydrogenated ZnO (101¯0) surface: First-principles study

ML, which is expected to significantly affect the properties of the spin splitting bands. Here, by using fully-relativistic first-principles calculations based on density-functional theory, we show that a substantial spin splitting band observed in the CBM is effectively controlled and tuned by applying the biaxial strain. We also find that these spin splitting bands induce spin textures exhibiting fully out-of-plane spin polarization in the opposite direction between the

Magnetism-Driven Electric Polarization of Multiferroic Quasi-One-Dimensional Ca3CoMnO6: First-Principles Study Using Density Functional Theory

K