相关论文: Understanding and reducing deleterious defects in …
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…
The presence of a point defect typically breaks the stoichiometry in a semiconductor. For example, a vacancy on an A-site in an AB compound makes the crystal B-rich. As the stoichiometry changes, so do the chemical potentials. While the…
We report an ab initio study of the semiconducting Mg2X (with X = Si, Ge) compounds and in particular we analyze the formation energy of the different point defects with the aim to understand the intrinsic doping mechanisms. We find that…
Lattice-matched heterovalent alloys and superlattices have some unique physical properties. For example, their band gap can change by a large amount without significant change in their lattice constants, thus they have great potential for…
The control of light through all-optical means is a fundamental challenge in nanophotonics and a key effect in optical switching and logic. The optical bistability effect enables this control and can be observed in various planar photonic…
The metastable 1$T'$ phase of layered transition metal dichalcogenides has recently attracted considerable interest due to electronic properties, possible topological electronic phases and catalytic activity. We report a comprehensive…
Positron annihilation spectroscopy is used to study point defects in Zn/1-x/Mn/x/GeAs/2/ crystals with low Mn content 0 < x < 0.042 with disordered zincblende and chalcopyrite structure. The role of negatively charged vacancies and…
The potential of Fe2TiSn full-Heusler compounds for thermoelectric applications has been suggested theoretically, but not yet grounded experimentally, due to the difficulty of obtaining reproducible, homogeneous, phase pure and defect free…
Density-functional-theory (DFT) calculations have been performed on the Li-Si and Li-Ge systems. Lithiated Si and Ge, including their metastable phases, play an important technological r\^ole as Li-ion battery (LIB) anodes. The calculations…
Crystal phase semiconductor heterostructures allow for electron confinement without uncertainties caused by chemical intermixing found in material heterostructures and are candidates for next generation optoelectronics devices ranging from…
The mechanism of the vacancy ordering in metastable cubic Ge-Sb-Te (c-GST) that underlies the ultrafast phase-change dynamics and prominent thermoelectric properties remains elusive. Achieving a comprehensive understanding of the…
The principal obstacle to long-time operation of silicon detectors at the highest energies in the next generation of experiments arises from bulk displacement damage which causes significant degradation of their macroscopic properties. The…
We quantitatively characterize the metastability in a multi-phase lattice Boltzmann model. The structure factor of density fluctuations is theoretically obtained and numerically verified to a high precision, for all simulated wave-vectors…
One of the basic optoelectronic characteristics is the absorption of any optoelectronic device or material. We present the characteristics of pure GaAs and the deviation of ideal spectra. Due to crystal defects, vacancies, impurities, etc.,…
High entropy alloys (HEAs) have captured much attention in recent years due to their conceivably improved radiation resistance compared to pure metals and traditional alloys. However, among HEAs, there are millions of design possibilities…
Continuum-buried defect states in semiconductors are generally expected to be optically inactive due to their strong coupling to continuum bands. Here, we show that such defects can instead host radiative electronic bound states in the…
An extensive search for low-energy lithium defects in crystalline silicon using density-functional-theory methods and the ab initio random structure searching (AIRSS) method shows that the four-lithium-atom substitutional point defect is…
Controlling the growth kinetics from the vapor phase has been a powerful paradigm enabling a variety of metastable epitaxial semiconductors such as Sn-containing group IV semiconductors (Si)GeSn. In addition to its importance for emerging…
In this work we have studied the defect structure and corresponding defect concentration investigations through the theoretical, experimental and computational works on B2-type Fe-Al alloys. We have used ab initio framework in order to…
Modeling point defects at an atomic scale requires careful treatment of the long-range atomic relaxations. This elastic field can strongly affect point defect properties calculated in atomistic simulations because of the finite size of the…