相关论文: Gate tunable current partition in graphene based t…
Bilayer graphene -- two coupled single graphene layers stacked as in graphite -- provides the only known semiconductor with a gap that can be tuned externally through electric field effect. Here we use a tight binding approach to study how…
Gapped bilayer graphene can support the presence of intragap states due to kink gate potentials applied to the graphene layers. Electrons in these states display valley-momentum locking, which makes them attractive for topological…
We investigate the conductance of an undoped graphene sheet with two metallic contacts and an electrostatically gated island (quantum dot) between the contacts. Our analysis is based on the Matrix Green Function formalism, which was…
The spatial arrangement of adsorbates deposited onto a clean surface in vacuum typically cannot be reversibly tuned. Here we use scanning tunneling microscopy to demonstrate that molecules deposited onto graphene field-effect transistors…
We examine the magnetic properties of the localized states induced by lattice vacancies in bilayer graphene with an unrestricted Hartree-Fock calculation. We show that with realistic values of the parameters and for experimentally…
Utilizing the Baym-Kadanoff formalism with the polarization function calculated in the random phase approximation, the dynamics of the $\nu=0$ quantum Hall state in bilayer graphene is analyzed. Two phases with nonzero energy gap, the…
We report a gate-tunable Josephson diode effect in hybrid nanowire junctions consisting of a spin-orbit-coupled semiconductor core coated with epitaxial ferromagnetic insulator and superconductor shells. The wires display a hysteretic…
The achievement of valley-polarized electron currents is a cornerstone for the realization of valleytronic devices. Here, we report on ballistic coherent transport experiments where two opposite quantum point contacts (QPCs) are defined by…
Further development of the field of all-electric spintronics requires the successful integration of spin transport channels with spin injector/generator elements. While with the advent of graphene and related 2D materials high performance…
We investigate theoretically properties of two-dimensional topological insulator constrictions both in the integer and fractional regimes. In the presence of a perpedicular magnetic field, the constriction functions as a spin filter with…
In equilibrium planer systems of Hall electrons, such as GaAs heterostructures and graphene, support two species of current counterflowing along the system edges, as observed recently in experiment using a nanoscale magnetometer. We examine…
Unipolar transport is demonstrated in a bilayer graphene with a series of p-n junctions and is controlled by electrostatic biasing by a comb-shaped top gate. The OFF state is induced by multiple barriers in the p-n junctions, where the band…
We argue that moir\'e bilayer graphene at charge neutrality hosts a continuous semimetal-to-insulator quantum phase transition that can be accessed experimentally by tuning the twist angle between the two layers. For small twist angles near…
The spin orbit effect in graphene is too muted to have any observable significance with respect to its application in spintronics. However, graphene technology is too valuable to be rendered impotent to spin transport. In this communication…
We have utilized the finite-difference approach to explore electron-tunneling properties in gapped graphene through various electrostatic-potential barriers changing from Gaussian to a triangular envelope function in comparison with a…
We investigate hybrid structures based on a bilayer quantum spin Hall system in proximity to an s-wave superconductor as a platform to mimic time-reversal symmetric topological superconductors. In this bilayer setup, the induced pairing can…
Knowledge of the topology of the electronic ground state of materials has led to deep insights to novel phenomena such as the integer quantum Hall effect and fermion-number fractionalization, as well as other properties of matter. Joining…
We study analytically and numerically the magnetotransport of strained graphene in a Corbino geometry gating in the presence of an external perpendicular magnetic field. The conductance of the Corbino disc of deformed graphene with a…
Tailor-made graphene nanostructures can exhibit symmetry-protected topological boundary states that host localized spin-$1/2$ moments. However, one frequently observes charge transfer on coinage metal substrates, which results in spinless…
Coherent manipulation of binary degrees of freedom is at the heart of modern quantum technologies. Graphene offers two binary degrees: the electron spin and the valley. Efficient spin control has been demonstrated in many solid state…