Related papers: Electronic states in cylindrical core-multi-shell …
We have performed atomistic simulations for helical multi-shell (HMS) Cu nanowires and nanotubes. Our investigation on HMS Cu nanowires and nanotubes has revealed some physical properties that were not dealt in previous works that…
Several methods are constructed for large-scale electronic structure calculations. Test calculations are carried out with up to 10^7 atoms. As an application, cleavage process of silicon is investigated by molecular dynamics simulation with…
Quantum dots tuned to atomic resonances represent an emerging field of hybrid quantum systems where the advantages of quantum dots and natural atoms can be combined. Embedding quantum dots in nanowires boosts these systems with a set of…
Atomistic quantum transport simulation of realistically large devices is computationally very demanding. The widely used mode space (MS) approach can significantly reduce the numerical cost but good MS basis is usually very hard to obtain…
In order to study heterostructures composed both of materials with strongly different parameters and of materials with narrow band gaps, we have developed an approach, which combines the spherical 8-band effective-mass Hamiltonian and the…
The structures of free-standing zirconium nanowires with 0.6$-$2.8 nm in diameter are systematically studied by using genetic algorithm simulations with a tight-binding many body potential. Several multi-shell growth sequences with…
A model for formation of helical multishell gold nanowires is proposed and is confirmed with the quantum mechanical molecular dynamics simulations. The model can explain the magic number of the helical gold nanowires in the multishell…
We report the nanoscale conductivity imaging of correlated electronic states in angle-aligned WSe2/WS2 heterostructures using microwave impedance microscopy. The noncontact microwave probe allows us to observe the Mott insulating state with…
We study the effect of semicore states on the self-energy corrections and electronic energy gaps of silicon, germanium and GaAs. Self-energy effects are computed within the GW approach, and electronic states are expanded in a plane-wave…
Nonlinear frequency conversion unlocks technologies ranging from telecommunications to quantum computation; however, weak nonlinearities and architectures that resist miniaturization currently limit devices. Here, we combine a…
Cylindrical magnetic nanowires are promising systems for the development of three-dimensional spintronic devices. Here, we simulate the evolution of magnetic states during fabrication of strongly-coupled cylindrical nanowires with varying…
Fundamental theories and practical methods for large-scale electronic structure calculations are given, in which the computational cost is proportional to the system size. Accuracy controlling methods for microscopic freedoms are focused on…
Using Kohn-Sham wave functions and their energy levels obtained by density-functional-theory total-energy calculations, the electronic structure of the two c(2x2) phases of Na on Al(001) are analysed; namely, the metastable hollow-site…
In this study, we designed and optimized the performance of pin junction GaAs/AlGaAs heterojunction nanowire solar cell arrays. It is done by performing coupled optoelectronic simulations to find the optimal doping for the GaAs core and…
We describe a technique to fabricate closely spaced electron-hole bilayers in GaAs-AlGaAs heterostructures. Our technique incorporates a novel method for making shallow contacts to a low density ($<10^{11}cm^{-2}$) 2-dimensional electron…
We investigated the electronic properties of strained Si/Ge core-shell nanowires along the [110] direction using first principles calculations based on density-functional theory. The diameter of the studied core-shell wire is up to 5 nm. We…
The electronic properties and nanostructure of InAs nanowires are correlated by creating multiple field effect transistors (FETs) on nanowires grown to have low and high defect density segments. 4.2 K carrier mobilities are ~4X larger in…
The new contribution of this paper is to develop a cylindrical representation of an already known multiphysics model for embedded nanowire superlattices (NWSLs) of wurtzite structure that includes a coupled, strain dependent 8-band…
Quantum-dot-in-nanowire systems constitute building blocks for advanced photonics and sensing applications. The electronic symmetry of the emitters impacts their function capabilities. Here, we study the fine structure of gallium-rich…
The existence of macroscopic shell structure of submicron metal clusters is known for several decades. Since the most studies provide theoretical analysis for clusters of spherical shape, the electron density inhomogeneities caused by shell…