相关论文: Shining light on short-range atomic ordering in se…
Energy bandgap largely determines the optical and electronic properties of a semiconductor. Variable bandgap therefore makes versatile functionality possible in a single material. In layered material black phosphorus, the bandgap can be…
Equiatomic CoCrNi medium entropy alloys are known for their unique properties linked to chemical short-range order (CSRO), crucial in both percolation processes and/or nucleation and growth processes influencing alloy passivation in aqueous…
The structure of Ge$_{22}$Ga$_3$Sb$_{10}$S$_{65}$ and Ge$_{15}$Ga$_{10}$Sb$_{10}$S$_{65}$ glasses was investigated by neutron diffraction (ND), X-ray diffraction (XRD), and extended X-ray absorption fine structure (EXAFS) measurements at…
Embedded germanium nanocrystals (NCs) in a silica host matrix are theoretically analyzed to identify their third-order bound-state nonlinearities. A rigorous atomistic pseudopotential approach is used for determining the electronic…
A redistribution of Cr atoms related to a phase decomposition (PD) caused by an isothermal annealing at 415 C in a 15.15 at%Cr Fe-Cr alloy was studied in an ex-situ way by the conversion electrons M\"ossbauer spectroscopy. Analysis of the…
Ultra-wide bandgap semiconductors such as \b{eta}-Ga2O3 are ideal materials for next-generation power electronic devices. Electronic and mechanical properties of \b{eta}-Ga2O3 can be tuned by alloying with other sesquioxides, notably Al2O3…
We present a real-space formulation for calculating the electronic structure and optical conductivity of such random alloys based on the Kubo-Greenwood formalism interfaced with the augmented space recursion (ASR) [A. Mookerjee, J. Phys. C:…
In Wigner-crystal states of two-dimensional electrons, the spin ordering remains poorly understood. The small energy differences between candidate spin orders make theoretical studies less reliable, and probing magnetic order at a nonzero…
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…
Chemical short-range order (SRO) provides new opportunities for tuning alloy properties, but conventional computational thermodynamics frameworks such as CALPHAD, based on Bragg-Williams mean-field approximations, cannot properly describe…
By applying an electric field perpendicular to a semiconductor quantum ring we show that it is possible to modify the single particle wave function between quantum dot (QD)-like to ring-like. The constraints on the geometrical parameters of…
Semiconductor material based on the rad-optic effect enables ultra-fast detection of X-rays and plays an important role in fusion diagnostics. Obtaining the accurate noise equivalent power (NEP) of the semiconductor ultrafast response…
The compositional dependence of the lowest direct and indirect band gaps in $\text{Ge}_{1-y}\text{Sn}_{y}$ has been determined from room-temperature photoluminescence measurements. This technique is particularly attractive for a comparison…
We use inelastic neutron scattering and molecular dynamics (MD) simulation to investigate the chemical short range order (CSRO), visible through prepeaks in the structure factors, and its relation to self diffusion in Al-Ni melts. As a…
Silicon crystallized in the usual cubic (diamond) lattice structure has dominated the electronics industry for more than half a century. However, cubic silicon (Si), germanium (Ge) and SiGe-alloys are all indirect bandgap semiconductors…
We have studied the band and optical properties of self-assembled quantum wires. In particular, the band structures and optical matrix elements of strained multiple quantum-wires (QWR's) are investigated theoretically via the effective…
By engineering atomic geometries composed of nearly 1000 atomic segments embedded in micro-resonators we observe Bragg resonances induced by the atomic lattice at the telecommunication wavelength. The geometrical arrangement of erbium atoms…
Multi-principal element alloys (MPEAs), commonly termed as medium- or high-entropy alloys containing three or more components in high concentrations, render a tunable chemical short-range order (SRO). Leveraging large-scale atomistic…
Here we analyze multiple symmetry-inequivalent atomic configurations across the entire composition range of the isovalent and isostructural Mo$_x$W$_{1-x}$S$_2$ alloy using density-functional theory and Monte Carlo simulations. Our results…
Disorder in crystals is rarely random, and instead involves local correlations whose presence and nature are hidden from conventional crystallographic probes. This hidden order can sometimes be controlled, but its importance for physical…