Related papers: Bandgap engineering of Cd1-xSrxO
Exact analytical results (in terms of Bessel functions) for the bandgaps, reflectance, and transmittance of one-dimensional photonic crystals with a sawtooth refractive index profile on the period are derived for the first time. This…
The bowing of the energy of the three lowest band-to-band transitions in $\beta$-(Al$_{x}$Ga$_{1-x}$)$_2$O$_3$ alloys was resolved using a combined density functional theory (DFT) and generalized spectroscopic ellipsometry (GSE) approach.…
We report a strong thickness dependence of the complex frequency-dependent optical dielectric function in epitaxial CaMnO3(001) thin films on SrTiO3(001), LaAlO3(001), and SrLaAlO4(001) substrates. A doubling of the peak value of the…
Optical spectroscopy was used to investigate the optical gap (2$\Delta $) due to charge ordering (CO) and related pseudogap developments with x and temperature (T) in La$_{1-x}$Ca$_{x}$MnO$_{3}$ (0.48 <= x <= 0.67). Surprisingly, we found…
We studied the band gap of {\beta}-PtO2 using first-principles calculations based on density functional theory (DFT). The results are obtained within the framework of generalized gradient approximation (GGA), GGA+U, GW and the hybrid…
Pre-edge features in X-ray absorption spectroscopy contain key information about the lowest excited states and thus on the most interesting physical properties of the system. In transition metal oxides they are particularly structured but…
We show that the infrared reflectance of the quasi-one dimensional charge-density-wave (CDW) conductor K0.3MoO3 (blue bronze) varies with position when a voltage greater than the CDW depinning threshold is applied. The spatial dependence…
In contrast to lead-based perovskites, double perovskites have attracted considerable interest due to their ability to modulate photovoltaic properties and high stability through elemental control. However, most double perovskites are…
We present an optical conductivity study of the multifold semimetal PdGa, performed in a broad spectral range (100 - 20000 cm-1; 12 meV - 2.5 eV) down to T = 10 K. The conductivity at frequencies below 4000 cm-1 is dominated by free…
Accurate band offsets are essential for predictive continuum modeling of nanostructures such as quantum wells and quantum dots formed in strained Si/Si1-xGex and Ge/Si1-xGex heterostructures. Experimental offset data for these systems…
This paper investigates a case study on measuring and controlling the first-order degree of spatial coherence under different coupling adjustments in the storage ring. The experimental findings are consistent with the predicted inverse…
The Kondo system CeRu$_4$Sn$_6$ shows a strong anisotropy in its electric, optic and magnetic properties. We employ density functional theory plus dynamical mean field theory and show that the predominant Ce-$f$ state has total angular…
The modification of the nature and size of bandgaps for III-V semiconductors is of strong interest for optoelectronic applications. Strain can be used to systematically tune the bandgap over a wide range of values and induce…
Compound semiconductor alloys of the type ABC find widespread applications as their electronic bulk band gap varies continuously with x, and therefore a tayloring of the energy gap is possible by variation of the concentration. We model the…
The power conversion efficiency of an ultrathin CIGS solar cell was maximized using a coupled optoelectronic model to determine the optimal bandgap grading of the nonhomogeneous CIGS layer in the thickness direction. The bandgap of the CIGS…
Electronic properties of graphene oxides enriched by the strong chemical bondings are investigated using first-principle calculations. They are very sensitive to the changes in the number of graphene layer, stacking configuration, and…
The cubic $Ia\bar{3}$ (BC8) and tetragonal $P4_32_12$ (ST12) high pressure modifications of Si and Ge are attractive candidates for applications in optoelectronic, thermoelectric or plasmonic devices. Si$_x$Ge$_{1-x}$ alloys in BC8/ST12…
Using density functional theory (DFT) within the local density approximation (LDA), we calculate the physical and electronic properties of PbTiO3 (PTO) and a series of hypothetical compounds PbTiO3-xSx x = 0.2, 0.25, 0.33, 0.5, 1, 2, and 3…
We compute the linear optical properties of different reconstructions of the clean and hydrogenated Si(100) surface within DFT-LDA, using norm-conserving pseudopotentials. The equilibrium atomic geometries of the surfaces, determined from…
We investigated the optical properties of 13 different dielectric materials (slide glass, quartz, Al2O3 (c-cut), DyScO3 (110), KTaO3 (001), LaAlO3 (001), (LaAlO3)0.3-(Sr2AlTaO6)0.7 (001) (LSAT), MgF2 (100), MgO (100), SiC, SrTiO3 (001),…