相关论文: Atomic Order in Non-Equilibrium Silicon-Germanium-…
Group IV alloys have been long viewed as homogeneous random solid solutions since they were first perceived as Si-compatible, direct-band-gap semiconductors 30 years ago. Such a perception underlies the understanding, interpretation and…
The local ordering of atoms in alloys directly has a strong impact on their electronic and optical properties. This is particularly relevant in nonrandom alloys, especially if they are deposited using far from the equilibrium processes, as…
We propose a microscopic method for modeling atomic ordering effects in multi-component solid solutions, which is based on minimizing the number of unfavorable interatomic bonds in the system. Atomic ordering effects are studied in the…
We present a thorough theoretical study of ordering phenomena in nitride ternary alloys GaInN, AlInN, and AlGaN. Using the Monte Carlo approach and energetics based on the Keating model we analyze the influence of various factors on…
The functional properties of semiconductors are typically controlled by tailoring their chemical composition and their state of strain, and by controlling their long-range structural order, including the presence of extended defects such as…
Recently, GeSn alloys have attracted much interest for direct-gap infrared photonics and as potential topological materials which are compatible with the semiconductor industry. However, for photonics, the high-Sn content required leads to…
Here we explore the use of scanning electron diffraction coupled with electron atomic pair distribution function analysis (ePDF) to understand the local order as a function of position in a complex multicomponent system, a hot rolled,…
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…
The growth and microstructural properties of ternary monolayers of two-dimensional hexagonal materials are examined, including both individual two-dimensional crystalline grains and in-plane heterostructures, multijunctions, or…
The full design of relevant systems for quantum applications, ranging from quantum simulation to sensing, is presented using a combination of atomistic methods. A prototypical system features a two-dimensional ordered distribution of spins…
Exploration of structure-property relationships as a function of dopant concentration is commonly based on mean field theories for solid solutions. However, such theories that work well for semiconductors tend to fail in materials with…
Of current importance for alloy design is controlling chemical ordering through processing routes to optimize an alloy's mechanical properties for a desired application. However, characterization of chemical ordering remains an ongoing…
The presence of short-range chemical order can be a key factor in determining the mechanical behavior of metals, but directly and unambiguously determining its distribution in complex concentrated alloy systems can be challenging. Here, we…
Group IV semiconductor alloys and heterostructures such as SiGe, GeSn, Ge/Si and SiGe:C have been widely used and under extensive research for applications in major microelectronic and photonic devices. In the growth and processing of these…
The thermodynamic stability of germanium tin $\mathrm{Ge_{1-x}Sn_x}$ alloys is investigated across the composition range $0 \le x \le 1$ by applying density functional theory (DFT) together with the cluster expansion formalism (CE). It is…
This paper studies short-range order (SRO) in the semiconductor alloy (GaN)$_{1-x}$(ZnO)$_x$. Monte Carlo simulations performed on a density functional theory (DFT)-based cluster expansion model show that the heterovalent alloys exhibit…
The structure of evaporated amorphous Ge$_x$Sb$_x$Te$_{100-2x}$ ($x =$ 6, 9, 13) alloys was investigated by neutron diffraction, X-ray diffraction and extended X-ray absorption spectroscopy (EXAFS) at the Ge, Sb and Te K-edges. Large scale…
The semimetallic Group V elements display a wealth of correlated electron phenomena due to a small indirect band overlap that leads to relatively small, but equal, numbers of holes and electrons at the Fermi energy with high mobility. Their…
Superconducting boron-doped silicon films prepared by gas immersion laser doping (GILD) technique are analyzed by atom probe tomography. The resulting three-dimensional chemical composition reveals that boron atoms are incorporated into…
We study nuclear relaxation in the presence of localized electrons in a two-dimensional electron gas in a disordered delta-doped semiconductor heterostructure and show that this method can reliably probe their magnetic interactions and…