Related papers: Suppressing backscattering of helical edge modes w…
An exactly solvable model for the decoherence of one and two-qubit states interacting with a spin-bath, in the presence of a time-dependent magnetic field is studied. The magnetic field is static along $\hat{z}$ direction and oscillatory in…
We consider a four-terminal setup of a two-dimensional topological insulator (quantum spin Hall insulator) with local tunneling between the upper and lower edges. The edge modes are modeled as helical Luttinger liquids and the…
We explicitly account for electron-electron interactions when modeling low-dimensional helical organic molecules. We show that competition between various hopping channels, together with interaction-induced double- and superexchange…
The question of whether the Coulomb interaction is strong enough to break the sublattice symmetry of un-doped graphene is discussed. We formulate a strong coupling expansion where the ground state of the Coulomb Hamiltonian is found exactly…
Dynamics of quantum entanglement shared between system spins which are connected to thermal equilibrium baths is studied. Central spin system comprises of the entangled spins, and is connected to baths and one of the bath has strong…
We study the two-body problem with a spatially modulated interaction potential using a two-channel model, in which the inter-channel coupling is provided by an optical standing wave and its strength modulates periodically in space. As the…
In this review, we discuss the decoherence and thermalization of a quantum spin system interacting with a spin bath environment, by numerically solving the time-dependent Schr\"{o}dinger equation of the whole system. The effects of the…
Spin orbit coupling changes graphene, in principle, into a two-dimensional topological insulator, also known as quantum spin Hall insulator. One of the expected consequences is the existence of spin-filtered edge states that carry…
We develop a theory for manipulating the effective band structure of interacting helical edge states realized on the boundary of two-dimensional time-reversal symmetric topological insulators. For sufficiently strong interaction, an…
We study a quantum dot coupled to two edge states of a quantum spin Hall insulator through electron tunnelings in the presence of a Rashba spin-orbital interaction induced by an external electric field. We show that if the electron…
We discuss how the crossovers in models like spin-boson model are changed by adding the coupling of the central spin to localised modes- the latter modelled as a 'spin bath'. These modes contain most of the environmental entropy and energy…
We study roles of electron correlations on topological insulators on the honeycomb lattice with the spin-orbit interaction. Accurate variational Monte Carlo calculations show that the increasing on-site Coulomb interactions cause a strong…
Quantum spin Hall (QSH) insulator with large gap is highly desirable for potential spintronics application. Here we realize electrically tunable QSH insulator with large gap in van der Waals heterobilayer of monolayer transition metal…
We consider the effect of Coulomb interactions in the propagation of electrons, prepared in arbitrary spin states, on chiral edge channels in the integer quantum Hall regime. Electrons are injected and detected at the same energy at…
We analyze the effect of a bath of spins interacting with a spin system in terms of the equation of motion technique. We show that this formalism can be used with general spin systems and baths, and discuss the concrete case of a Quantum…
We present analysis of a single channel interacting quantum wire problem in the presence of spin-orbit interaction. The spin-orbit coupling breaks the spin-rotational symmetry from SU(2) to U(1) and breaks inversion symmetry. The low-energy…
Open quantum systems are subject to interaction with their surrounding environment. In many applications, at low temperatures, quantum environments fall into two universality classes of models: Caldeira-Leggett oscillator bath models and…
We study the entanglement dynamics for a two-spin system coupled to a spin environment of different configurations by z-x type interaction. The models considered in this paper are solved both analytically and numerically giving rise to some…
Conventional wisdom holds that, in the simplest time-reversal-symmetric setting, strongly coupling two QSH layers yields a trivial $\mathbb Z_2$ phase and no protected topological edge states. We demonstrate that, in a regime with…
We study the effects of quantum fluctuations on a non-coplanar tetrahedral spin structure, which has a scalar chiral order, in the spin-1/2 multiple-spin exchange model with up to the six-spin exchange interactions on a triangular lattice.…