Related papers: In-plane noncollinear exchange coupling mediated b…
We present direct experimental evidence for nonlocal transport in HgTe quantum wells in the quantum spin Hall regime, in the absence of any external magnetic field. The data conclusively show that the non-dissipative quantum transport…
We study the thermoelectric response of a device containing a pair of helical edge states contacted at the same temperature $T$ and chemical potential $\mu$ and connected to an external reservoir, with different chemical potential and…
We investigate the long-range behavior and size dependence of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction in hexagonal and triangular graphene nanoflakes with zigzag and arm-chair edges. We employ the tight-binding model with exact…
We derive a generalization of the RKKY interaction to semiconductors using perturbation theory on a non-degenerated two-impurity Anderson model. In metals the interaction is mediated by excitations of free carriers over the Fermi-energy. In…
The promotion of collinear classical spin configurations as well as the enhanced tendency towards nearest-neighbor clustering of the quantum spins are typical features of the frustrating isotropic three-body exchange interactions in…
Due to nonzero intrinsic spin-orbit interaction in buckled honeycomb crystal structures, silicene and germanene exhibit interesting topological properties, and are therefore candidates for the realization of the quantum spin Hall effect. We…
We study theoretically the statistical properties of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction between localized magnetic moments in a disordered two-dimensional electron gas with both Rashba and Dresselhaus spin-orbit couplings.…
In this paper, we investigate the Kane-Mele model and endeavor to demonstrate, through analytical calculations, how the presence of topological edge states influences the RKKY interaction. We illustrate that the effect diminishes as one…
We study theoretically the two interacting one-dimensional helical modes at the edges of the quantum spin Hall systems. A new type of inter-edge correlated liquid (IECL) without the spin gap is found. This liquid shows the diverging density…
We study quantum spin Hall insulators with local Coulomb interactions in the presence of boundaries using dynamical mean field theory. We investigate the different influence of the Coulomb interaction on the bulk and the edge states.…
We describe a device where the non-local spin-spin interaction between two quantum dots can be turned on and off and even changed sign with a very small magnetic field. The setup consists of two quantum dots at the edge of two…
A non-interacting electron gas on a one-dimensional ring is considered at finite temperatures. The localized spin is embedded at some point on the ring and it is assumed that the interaction between this spin and the electrons is the…
We investigate the magnetic behavior of nuclear spins embedded in a 2D interacting electron gas using a Kondo lattice model description. We derive an effective magnetic Hamiltonian for the nuclear spins which is of the RKKY type and where…
We study a one-dimensional helical system with random Rashba spin-orbit coupling. Using renor- malization group methods, we derive a consistent set of flow equations governing the important con- trol parameters of the backscattering…
We study theoretically the low-energy hole states of Ge/Si core/shell nanowires. The low-energy valence band is quasidegenerate, formed by two doublets of different orbital angular momenta, and can be controlled via the relative shell…
We discuss the transport properties of a quantum spin-Hall insulator with sizable Rashba spin-orbit coupling in a disk geometry. The presence of topologically protected helical edge states allows for the control and manipulation of spin…
Combining an analytical and numerical approach we investigate the dispersion of the topologically protected spin-filtered edge-states of the Quantum Spin Hall state on honeycomb and ruby nets with zigzag (ZZ) and armchair (AC) edges. We…
We explore the phases exhibited by an interacting quantum spin Hall edge state in the presence of finite chemical potential (applied gate voltage) and spin imbalance (applied magnetic field). We find that the helical nature of the edge…
We propose a generalized Dirac fermion description for the electronic state of graphene terminated by a zigzag edge. This description admits a spin-orbit coupling needed to preserve time-reversal invariance of the zigzag confinement,…
For a double quantum dot system in a parallel geometry, we demonstrate that by combining the effects of a flux and driving an electrical current through the structure, the spin correlations between electrons localized in the dots can be…