相关论文: Fermi Level and Light Driven Defect Generation in …

In this paper we discuss the application of current it ab initio computer simulation techniques to hydrogenated amorphous silicon (a-Si:H). We begin by discussing thermal fluctuation in the number of coordination defects in the material,…

We study by means of first-principles pseudopotential method the coordination defects in a-Si and a-Si:H, also in their formation and their evolution upon hydrogen interaction. An accurate analysis of the valence charge distribution and of…

Elemental substitution is a proven method of Fermi level tuning in topological insulators, which is needed for device applications. Through static and time resolved photoemission, we show that in MnBi$_2$Te$_4$, elemental substitution of Bi…

Moisture- and temperature-activated corrosion of metal fingers, mechanical stress induced delamination, and failure of solder bonds rank among the leading failure mechanisms of solar modules. The physics of moisture ingress, diffusion and…

We introduce a method to calculate defect-assisted Shockley-Read-Hall (SRH) recombination rates in imperfect semiconductors from first principles. The method accounts for the steady state recombination dynamics under given non-equilibrium…

The creation of point defects in the crystal lattices of various semiconductors by subthreshold events has been reported on by a number of groups. These observations have been made in great detail using sensitive electrical techniques but…

We measure charge transport in hydrogenated amorphous silicon (a-Si:H) using a nanometer scale silicon MOSFET as a charge sensor. This charge detection technique makes possible the measurement of extremely large resistances. At high…

The integration of III-V on silicon is still a hot topic as it will open up a way to co-integrate Si CMOS logic with photonic vices. To reach this aim, several hurdles should be solved, and more particularly the generation of antiphase…

Defects in crystalline silicon consisting of a silicon self-interstitial atom and one, two, three, or four hydrogen atoms are studied within density-functional theory (DFT). We search for low-energy defects by starting from an ensemble of…

It is known that silicon is an indirect band gap material, reducing its efficiency in photovoltaic applications. Using surface plasmons in metallic nanoparticles embedded in a solar cell has recently been proposed as a way to increase the…

Formation energies of charged point defects in semiconductors are calculated using periodic supercells, which entail a divergence arising from long-range Coulombic interactions. The divergence is typically removed by the so-called jellium…

We employ ab initio molecular dynamics to simulate the response of hydrogenated amorphous silicon to light exposure (Staebler-Wronski effect). We obtain improved microscopic understanding of PV operation, compute the motion of H atoms, and…

The enhancement of the fill factor in the current generation of perovskite solar cells is the key for further efficiency improvement. Thus, methods to quantify the fill factor losses are urgently needed. A classical method to quantify Ohmic…

Intrinsic hydrogenated amorphous silicon films can provide outstanding surface passivation of crystalline silicon wafer surfaces. This quality of Intrinsic hydrogenated amorphous silicon makes it valuable in heterojunction with intrinsic…

By application of the ac admittance spectroscopy method, the defect state energy distributions were determined in CdTe incorporated in thin film solar cell structures concluded on ZnO, ZnSe, and ZnS buffer layers. Together with the…

A phenomenological model was developed to explain quantitatively, without free parameters, the production of primary defects in silicon after particle irradiation, the kinetics of their evolution toward equilibrium and their influence on…

In neutral dense electron-hole (e-h) systems at low temperatures, theory predicts Cooper-pair-like excitons at the Fermi energy and a BCS-like exciton condensation. Optical excitation allows creating e-h systems with the densities…

An H atom inserted into hydrogen monolayer on the Si(100)-2x1 surface has been studied using the density functional theory. Hydrogen-induced defects were considered in their neutral, negative, and positive charge states. It was found that…

Three-dimensional topological semimetals host a range of interesting quantum phenomena related to band crossing that give rise to Dirac or Weyl fermions, and can be potentially engineered into novel quantum devices. Harvesting the full…

It is known from density functional theory (DFT) calculations that RhSi has a multifold degenerate Dirac point at the Fermi energy, with the dominant states in the low-energy region displaying mostly Rh $d$ character. Using DFT+U, we…