相关论文: Models of core reconstruction for the 90-degree pa…

We investigate the energetics of the single-period and double-period core reconstructions of the 90-degree partial dislocation in the homopolar semiconductors C, Si, and Ge. The double-period geometry is found to be lower in energy in all…

We investigate the physics of the core reconstruction and associated structural excitations (reconstruction defects and kinks) of dislocations in silicon, using a linear-scaling density-matrix technique. The two predominant dislocations…

We suggest that the commonly-accepted core structure of the 90-degree partial dislocation in Si may not be correct, and propose instead a period-doubled structure. We present LDA, tight-binding, and classical Keating-model calculations, all…

Kink defects in the 90-degree partial dislocation in silicon are studied using a linear-scaling density-matrix technique. The asymmetric core reconstruction plays a crucial role, generating at least four distinct kink species as well as…

Atomic-scale calculations for the dynamics of the 90$^0$ partial glide dislocation in silicon are made using the effective-medium tight-binding theory. Kink formation and migration energies for the reconstructed partial dislocation are…

We study elementary semiconductors and insulators that are symmetric under spatial inversion: silicon, diamond, germanium, and black phosphorene. These materials are ideal candidates for realizing obstructed atomic insulators, which differ…

In a recent Letter [N. Lehto and S. Oberg, Phys. Rev. Lett. 80, 5568 (1998)], Lehto and Oberg investigated the effects of strain fields on the core structure of the 90-degree partial dislocation in silicon, especially the influence of the…

Although (103) is a stable nominal orientation for both silicon and germanium, experimental observations revealed that in the case of silicon this surface remains disordered on an atomic scale even after careful annealing. We report here a…

Twin growth in hexagonal close-packed zirconium is investigated at the atomic scale by modeling the various disconnections that can exist on twin boundaries. Thanks to a coupling with elasticity theory, core energies are extracted from…

By using the state-of-the-art microscopy and spectroscopy in aberration-corrected scanning transmission electron microscopes, we determine the atomic arrangements, occupancy, elemental distribution, and the electronic structures of…

Large-scale atomistic calculations, using empirical potentials for modeling semiconductors, have been performed on a stressed system with linear surface defects like steps. Although the elastic limits of systems with surface defects remain…

Hexagonal SiGe is a promising material for combining electronic and photonic technologies. In this work, the energetic, structural, elastic and electronic properties of the hexagonal polytypes (2$H$, 4$H$ and 6$H$) of silicon and germanium…

Without our ability to model and manipulate the band structure of semiconducting materials, the modern digital computer would be impractically large, hot, and expensive. In the undergraduate QM curriculum, we studied the effect of spatially…

We consider a two-component scaling picture for the resistivity of two-dimensional (2D) weakly disordered interacting electron systems at low temperature with the aim of describing both the vicinity of the bifurcation and the low resistance…

Analysis is given of the changes of dislocation motion modes with stress and temperature variation. Different regimes of dislocation kink pair formation and spreading (motion in the random potential, in the field of random forces, the…

The suitability of molecular statics (MS) simulations to model the structure of 90{\deg} glide set partial dislocation cores in GaAs is analyzed. In the MS simulations the atomic positions are iteratively relaxed by energy minimization, for…

We introduce an approach to exploit the existence of multiple levels of description of a physical system to radically accelerate the determination of thermodynamic quantities. We first give a proof of principle of the method using two…

We show that a double quantum-dot system made of diluted magnetic semiconductor behaves unlike usual molecules. In a semiconductor double quantum dot or in a diatomic molecule, the ground state of a single carrier is described by a…

Silicon nanowires grown along the <100>-direction with a bulk Si core are studied with density functional calculations. Two surface reconstructions prevail after exploration of a large fraction of the phase space of nanowire…

We present a comprehensive study of the band alignments of two-dimensional (2D) semiconducting materials and highlight the possibilities of forming momentum-matched type I, II and III heterojunctions; an enticing possibility being atomic…