Related papers: Optical properties of cubic and rhombohedral GeTe
In this paper we study the size effects of the ferroelectric nanotube phase diagrams and polar properties allowing for effective surface tension and depolarization field influence. The approximate analytical expression for the…
It is shown that small inclusions of a low absorbing metal can have a dramatic effect on the photonic band structure. In the case of diamond and zinc-blende photonic crystals, several complete photonic band gaps (CPBG's) can open in the…
The optical conductivity of MgB$_2$ has been determined on a dense polycrystalline sample in the spectral range 6 meV - 4.6 eV using a combination of ellipsometric and normal incidence reflectivity measurements. $\sigma_{1}(\omega)$…
The optical properties of periodic electromagnetic metamaterials are considered as functions of their relative unit cell size $d / \lambda$. The reflection $R$ and transmission $T$ coefficients are numerically calculated for some realistic…
We have carried out optical-absorption and reflectance measurements at room temperature in single crystals of AWO4 tungstates (A = Ba, Ca, Cd, Cu, Pb, Sr, and Zn). From the experimental results their band-gap energy has been determined to…
Measurements by high-resolution electron energy-loss spectroscopy (HREELS) of NaxCoO2 reveal spectral features that differ remarkably between the metallic Na0.33CoO2 and the charge-ordered insulator Na0.5CoO2. Calculations by density…
Thin films of CdTe were deposited on glass substrates by thermal evaporation. From the XRD measurements itis found that the films are of zinc-blende-type structure. Transmittance, absorption, extinction, and refractive coefficients are…
Rhombohedral graphite features peculiar electronic properties, including persistence of low-energy surface bands of a topological nature. Here, we study the contribution of electron-hole excitations towards inelastic light scattering in…
In$_2$Se$_3$ is a semiconductor material that can be stabilized in different crystal structures (at least one 3D and several 2D layered structures have been reported) with diverse electrical and optical properties. This feature has plagued…
Three dimensional (3D) topological Dirac materials are under intensive study recently. The layered compound ZrTe$_5$ has been suggested to be one of them by transport and ARPES experiments. Here, we perform infrared reflectivity measurement…
We perform an in-plane optical spectroscopy measurement on high quality FeSe single crystals grown by a vapor transport technique. Below the structural transition at $T_{\rm s}\sim$90 K, the reflectivity spectrum clearly shows a gradual…
Wide band gap materials are particularly relevant at high temperatures. The band gap shrinkage at higher temperatures prevents device applications with narrow band gap semiconductors. Considering $\alpha$-phase strontium cyanurate as a…
We calculate the photonic band gap of triply periodic bicontinuous cubic structures and of tubular structures constructed from the skeletal graphs of triply periodic minimal surfaces. The effect of the symmetry and topology of the periodic…
By using pseudopotential method with local spin density functional approximation, the electronic band structures of Na$_{x}$CoO$_{2}$ are calculated for $x=0.25$, 0.5, 0.75, and $x=1$ in the presence of the structure relaxations. As…
With an MBE technique, a Si/Ge heterostructures are prepared containing layers of nanostructured Ge with quantum dots of size of several nanometers. The effective conductivity of the layers is determined by a quasioptical…
By combining scanning probe microscopy with Raman and x-ray photoelectron spectroscopies, we investigate the evolution of CVD-grown graphene/Ge(001) as a function of the deposition temperature in close proximity to the Ge melting point,…
Hexagonal SiGe is a promising material for combining electronic and photonic technologies. In this work, the energetic, structural, elastic and electronic properties of the hexagonal polytypes (2$H$, 4$H$ and 6$H$) of silicon and germanium…
Effects of electron-beam processing on the structure and mechanical properties of poly-ether-ether ketone (PEEK) were studied by XRD and tribological tests. An ambiguous change in the mechanical properties of the irradiated samples was…
We have evaluated the energies required to twist carbon nanotubes (NTs), and investigated the effects of these distortions on their electronic structure and electrical properties. The computed distortion energies are high, indicating that…
The authors report micro-Raman investigation of changes in the single and bilayer graphene crystal lattice induced by the low and medium energy electron-beam irradiation (5 and 20 keV). It was found that the radiation exposures results in…