Related papers: Mechanical strain in capped and uncapped self-asse…
We have experimentally investigated the hole states in a gated vertical strained Si/SiGe quantum dot. We demonstrate the inhomogeneous strain relaxation on the lateral surface creates a ring-like potential near the perimeter of the dot,…
We investigate the initial stage of the 2D-3D transition of strained Ge layers deposited on pit-patterned Si(001) templates. Within the pits, which assume the shape of inverted, truncated pyramids after optimized growth of a Si buffer…
An atomistic model based on the Keating potential and the conjugate gradient method are used for simulation of the strain fields for single Ge/Si quantum dots. Calculations are performed in the cluster approximation using clusters…
We study the low-energy spectrum of a single hole confined in a planar Ge quantum dot (QD) within the effective-mass formalism. The QD is sandwiched between two GeSi barriers of finite potential height grown along the [001] direction. To…
We present the results of a systematic study using the density functional theory (within the local density approximation) of the effects of biaxial strain and composition on the self-diffusion of Si and Ge in SiGe alloys diffusing by a…
Quantum dot lasers have been the focus of researchers due to their interesting optical properties owing to quantum confinement of carriers. In epitaxial quantum dots formed on a substrate, band-edge diagrams sound to more complex than…
Germanium (Ge) quantum wells are emerging as versatile platforms for quantum devices, supporting high-quality spin qubits and integration with superconducting leads. These applications benefit from strong intrinsic spin-orbit interaction…
We use an efficient projection scheme for the Fock operator to analyze the size dependence of silicon quantum dots (QDs) electronic properties. We compare the behavior of hybrid, screened hybrid and local density functionals as a function…
This study explores the optical properties of quantum dots doped with a Ni$^{2+}$ ion that interacts with a charged exciton. Systematic magneto-optical analysis reveals that the strain distribution at the Ni$^{2+}$ site significantly…
A novel picture of the quasiparticle (QP) gap in prototype semiconductors Si and Ge emerges from an analysis based on all-electron, self-consistent, GW calculations. The deep-core electrons are shown to play a key role via the exchange…
Embedding quantum dots (QDs) on nanowire (NW) sidewalls allows the integration of multi-layers of QDs into the active region of radial p-i-n junctions to greatly enhance light emission/absorption. However, the surface curvature makes the…
The epitaxial growth of germanium on silicon leads to the self-assembly of SiGe nanocrystals via a process that allows the size, composition and position of the nanocrystals to be controlled. This level of control, combined with an inherent…
Silicon quantum dots are nanomaterials that are attractive candidates for photovoltaic applications. Doping of these materials creates p-n junctions and is important for solar cells. In this work, we present a first-principles study of the…
Density functional theory has been employed to study graphene on the (111), (100) and (110) surfaces of silicon (Si) substrates. There are several interesting findings. First, carbon atoms in graphene form covalent bonds with Si atoms, when…
Self-assembled quantum dot (QD) solids are a highly tunable class of materials with a wide range of applications in solid-state electronics and optoelectronic devices. In this perspective, we highlight how the presence of microscopic…
In this work we report on a self-assembled growth of a Ge quantum dot lattice in a single 600-nm-thick Ge+Al2O3 layer during magnetron sputtering deposition of a Ge+Al2O3 mixture at an elevated substrate temperature. The self-assembly…
Applying external strain is an efficient way to manipulate the site preference of dopants in semiconductors, however, the validity of the previous continuum elastic model for the strain influence on the doping forma- tion energy is still…
Silicon carbide is widely used in electronics, ceramics, and renewable energy due to its exceptional hardness and resistance. In this study, we investigate the effects of hydrostatic and uniaxial pressure (both compressive and tensile) on…
Lattice mismatch in layered semiconductor structures with submicron length scales leads to extremely high nonuniform strains. This paper presents a finite element technique for incorporating the effects of the nonuniform strain into an…
I present a systematic study of self-assembled InAs/InP and InAs/GaAs quantum dots single particle and many body properties as a function of quantum dot-surrounding matrix valence band offset. I use an atomistic, empirical tight-binding…