Related papers: A controllable valley polarization in Graphene
Resonant electronic transmission through graphene-based double barriers (wells) is studied as a function of the incident wave vector, the widths and heights (depths) of the barriers (wells), and the separation between them. Resonant…
Bilayer graphene subjected to perpendicular magnetic and electric fields displays a subtle competition between different symmetry broken phases, resulting from an interplay between the internal spin and valley degrees of freedom. The…
The tunable magnetism at graphene edges with lengths of up to 48 unit cells is analyzed by an exact diagonalization technique. For this we use a generalized interacting one-dimensional model which can be tuned continuously from a limit…
Electrons are offered a valley degree of freedom in presence of particular lattice structures. Manipulating valley degeneracy is the subject matter of an emerging field of investigation, mostly focused on charge transport in graphene. In…
We show that strained or deformed honeycomb lattices are promising platforms to realize fractional topological quantum states in the absence of any magnetic field. The strained induced pseudo magnetic fields are oppositely oriented in the…
We propose a device for the generation of valley polarized electronic current in bilayer graphene. By analyzing the response of this material to intense terahertz frequency light in the presence of a transverse electric field, we…
We show that chiral edge states in graphene under Quantum Hall effect conditions can be selectively probed and excited by terahertz or infrared radiation with single-quasiparticle sensitivity without affecting bulk states. Moreover,…
A population imbalance at different valleys of an electronic system lowers its effective rotational symmetry. We introduce a technique to measure such imbalance - a valley polarization - that exploits the unique fingerprints of this…
Valley, the energy extrema in the electronic band structure at momentum space, is regarded as a new degree of freedom of electrons, in addition to charge and spin. The studies focused on valley degree of freedom now form an emerging field…
A tunable graphene-based reflective cell operating at THz is proposed for use in reconfigurable-beam reflectarrays, or similarly to implement the so-called generalized law of reflection. The change in the complex conductivity of graphene…
Topological materials may exhibit Hall-like currents flowing transversely to the applied electric field even in the absence of a magnetic field. In graphene superlattices, which have broken inversion symmetry, topological currents…
We consider the scattering of Dirac particles in graphene due to the superposition of an external magnetic field and mechanical strain. As a model for a graphene nanobubble, we find exact analytical solutions for single-particle states…
We demonstrate theoretically how local strains in graphene can be tailored to generate a valley polarized current. By suitable engineering of local strain profiles, we find that electrons in opposite valleys (K or K') show different…
The Corbino geometry allows one to investigate the propagation of electric current along a p-n interface in ballistic graphene in the absence of edge states appearing for the familiar Hall-bar geometry. Using the transfer matrix in the…
The control and manipulation of the valley and spin degrees of freedom have received great interests in fundamental studies and advanced information technologies. Compared with magnetic means, it is highly desirable to realize more…
We investigate superconducting pairing tendencies of a two-dimensional electron fluid with both valley and spin degrees of freedom, both without and in the presence of an in-plane magnetic field. We present suggestive theoretical arguments…
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…
Dirac electrons in graphene have a valley degree of freedom that is being explored as a carrier of information. In that context of "valleytronics" one seeks to coherently manipulate the valley index. Here we show that reflection from a…
The discovery of the integer quantum Hall effect in the early eighties of the last century, with highly precise quantization values for the Hall conductance in multiples of $e^2/h$, has been the first fascinating manifestation of the…
Graphene has evolved as a platform for quantum transport that can compete with the best and cleanest semiconductor systems. Recently, many interesting local properties of carrier transport in graphene have been investigated by various…