相关论文: Metallic behaviour in SOI quantum wells with stron…
We determine the structure and melting behavior of supported metallic clusters using an ab initio density-functional-based treatment of intracluster interactions and an approximate treatment of the surface as an idealized smooth plane…
While conventional semiconductor technology relies on the manipulation of electrical charge for the implementation of computational logic, additional degrees of freedom such as spin and valley offer alternative avenues for the encoding of…
Electron states are studied for quantum dots in a strained Si quantum well, taking into account both valley and orbital physics. Realistic geometries are considered, including circular and elliptical dot shapes, parallel and perpendicular…
Valleytronics aims to control electrons in a valley-specific manner for quantum information manipulation. Due to their strong in-plane anisotropy, which enables polarization-controlled optical transitions to distinct nondegenerate valleys,…
In this letter we study the valley degeneracy splitting of the transition-metal dichalcogenides monolayer by first-principles calculations. The local magnetic moments are introduced into the system when the transition-metal atoms are…
In a recent work, new two-dimensional materials, the monolayer MoSi$_{2}$N$_{4}$ and WSi$_{2}$N$_{4}$, have been successfully synthesized in experiment, and several other monolayer materials with the similar structure, such as…
Electron valleys in transition-metal dichalcogenide monolayers drive novel physics and allow designing multifunctional architectures for applications. We propose to manipulate the electron valleys in these systems for spin/valley filter and…
In the ballistic regime, the metallic temperature dependence of the conductivity in a two-dimensional electron system in silicon is found to change non-monotonically with the degree of spin polarization. In particular, it fades away just…
We present the theory and measurement of valley splitting in a quantum point contact (QPC) in a modulation doped Si/SiGe heterostructure. Our measurements are performed on a submicron Schottky-gated device. An effective mass theory is…
Magnetism and topology are two major areas of condensed matter physics. The combination of magnetism and topology gives rise to more novel physical effects, which have attracted strongly theoretical and experimental attention. Recently, the…
We study the quantum diffusive transport of multivalley massive Dirac cones, where time-reversal symmetry requires opposite spin orientations in inequivalent valleys. We show that the intervalley scattering and intravalley scattering can be…
The surprisingly rich physics of a single Coulomb-blockaded metallic island, when coupled to quantum Hall edge channels, is now well established -- giving rise to charge fractionalization and multi-channel quantum impurity behavior. Here,…
Two-dimensional semimetals with tilted Dirac cones in the electronic band structure are shown to exhibit spatial separation of carriers belonging to different valleys under illumination. In stark contrast to gapped Dirac materials this…
Scattering processes by the interface roughness in a quantum well in a quantizing magnetic field are considered. An expression for the scattering rate is derived for a magnetic field tilted relative to the quantum well layers. By analyzing…
The growth and the density dependence of the low temperature mobility of a series of two-dimensional electron systems confined to un-intentionally doped, low extended defect density InAs quantum wells with Al$_{1-x}$Ga$_{x}$Sb barriers are…
The two-dimensional electron gas is of fundamental importance in quantum many-body physics. We study a minimal extension of this model with $C_4$ (as opposed to full rotational) symmetry and an electronic dispersion with two valleys with…
The goal of this paper is to highlight several issues which are most crucial for the understanding of the ``metal-insulator transition'' in two dimensions. We discuss some common problems in interpreting experimental results on high…
In this paper, we study the scattering and diffraction phenomena in time-modulated metamaterials of metallic nature by means of Floquet equivalent circuits. Concretely, we focus on a time-periodic screen that alternates between "metal" and…
In crystals, energy band extrema in momentum space can be identified by their valley index. The internal quantum degree of freedom associated with valley pseudospin indices can act as a useful information carrier analogous to electronic…
Density-functional calculations are used to identify one-atom-thick metallic In overlayers on the Si(111) surface, which have long been sought in quest of the ultimate two-dimensional (2D) limit of free-electron-like metallic properties. We…