Related papers: Low-energy trions in graphene quantum dots

In this paper we study in detail different types of topological solitons which are possible in bilayer quantum Hall systems at filling fraction $\nu =1$ when spin degrees of freedom are included. Starting from a microscopic Hamiltonian we…

We present a supersymmetric description of the quantum Hall effect (QHE) in graphene. The noninteracting system is supersymmetric separately at the so-called K and K' points of the Brillouin zone corners. Its essential consequence is that…

Using the approach of low-energy effective field theory, the phase diagram is studied for a mixture of two species of pseudospin-$\1/2$ Bose atoms with interspecies spin-exchange. There are four mean-field regimes on the parameter plane of…

The quantum Hall (QH) effect, the quantum spin Hall (QSH) effect and the quantum valley Hall (QVH) effect are three peculiar topological insulating phases in graphene. They are characterized by three different types of edge states. These…

We study the effects of electron-electron interactions on the transport properties of a junction of three quantum wires enclosing a magnetic flux. The wires are modeled as single channel spin-1/2 Tomonaga-Luttinger liquids. The system…

Tunneling of quasiparticles between two nearly-aligned graphene sheets produces resonant current-voltage characteristics because of the quasi-exact conservation of in-plane momentum. We claim that, in this regime, vertical transport in…

Trions -- Coulomb-bound three-particle excitations composed of two like-charge carriers and one oppositely charged carrier -- are central quasiparticles in two-dimensional semiconductors. Reduced dielectric screening and quantum confinement…

The advent of few-layer graphenes has given rise to a new family of two-dimensional systems with emergent electronic properties governed by relativistic quantum mechanics. The multiple carbon sublattices endow the electronic wavefunctions…

We investigate the spin of a multielectron GaAs quantum dot in a sequence of nine charge occupancies, by exchange coupling the multielectron dot to a neighboring two-electron double quantum dot. For all nine occupancies, we make use of a…

We report the findings of fractional topological states in one-dimensional periodically modulated quantum spin chains with up to third neighbor interactions. By exact numerical studies, we demonstrate the existence of topologically…

(001) Si spin qubits are being intensively studied because they have structures similar to that of CMOS devices currently being produced, and thus have the advantage of utilizing state-of-the-art miniaturization, integration, and…

Bilayer graphene in a magnetic field supports eight zero-energy Landau levels, which, as a tunable band gap develops, evolve into two nearly-degenerate quartets separated by the band gap. A close look is made into the properties of such an…

We report on recent results obtained by the above collaboration on the collision processes involving three nucleons, where we pay particular attention on the dynamical role of the pion. After discussing the case at intermediate energies,…

The interaction of light and swift electrons has enabled phase-coherent manipulation and acceleration of electron wavepackets. Here we investigate this interaction in a new regime where low-energy electrons (~20-200 eV) interact with a…

The interaction between itinerant electrons and localized spins is key to a wide range of electronic phenomena. Of particular interest is the regime where the interacting electrons exhibit both spin and valley degeneracy, resulting in SU(4)…

Coherent nonlinear tripartite interactions are critical for advancing quantum simulation and information processing in hybrid quantum systems, yet they remain experimentally challenging and still evade comprehensive exploration. Here, we…

Due to its fourfold spin-valley degeneracy, graphene in a strong magnetic field may be viewed as a four-component quantum Hall system. We investigate the consequences of this particular structure on a possible, yet unobserved, fractional…

We demonstrate theoretically that quantum dots in bilayers of graphene can be realized. A position-dependent doping breaks the equivalence between the upper and lower layer and lifts the degeneracy of the positive and negative momentum…

Electron spins confined in silicon quantum dots are promising candidates for large-scale quantum computers. However, the degeneracy of the conduction band of bulk silicon introduces additional levels dangerously close to the window of…

We study theoretically many-body properties of magic-angle twisted bilayer graphene for different doping levels. Our investigation is focused on the emergence, stability, and manifestations of nematicity of the ordered low-temperature…