99 citations · 455 across the 29 of their papers we have counts for
22 papers · 1 filter
Edge-state transport in gapped bilayer graphene
Jesús Arturo Sánchez-Sánchez, Thomas Stegmann
We investigate electronic transport in gapped bilayer graphene (gBLG) devices. For certain edge terminations -typically a combination of zigzag, armchair, and bearded types - we ob…
Electronic transport and anti-super-Klein tunneling in few-layer black phosphorous
Jorge Alfonso Lizarraga-Brito, Armando Arciniega-Gutiérrez, Yonatan Betancur-Ocampo +1
The electronic transport in few-layer black phosphorus (FLBP) nanoribbons is studied theoretically. The system is modeled on the basis of band-structures, which have been measured…
Edge-state transport in twisted bilayer graphene
Jesús Arturo Sánchez-Sánchez, Montserrat Navarro-Espino, José Eduardo Barrios-Vargas +1
We investigate the electronic structure and transport properties of twisted bilayer graphene (TBLG) at a twist angle of . Using a combination of molecular d…
Atomically thin current pathways in graphene through Kekulé-O engineering
Santiago Galván y García, Yonatan Betancur-Ocampo, Francisco Sánchez-Ochoa +1
We demonstrate that the current flow in graphene can be guided on atomically thin current pathways by means of the engineering of Kekulé-O distortions. A grain boundary in these di…
Electronic transport in bent carbon nanotubes
Eric Kleinherbers, Thomas Stegmann, Nikodem Szpak
We study the electronic transport through uniformly bent carbon nanotubes. For this purpose, we describe the nanotube with the tight-binding model and calculate the local current f…
Graphene nanodrums as valleytronic devices
Walter Ortiz, Nikodem Szpak, Thomas Stegmann
We investigate the electronic transport in graphene nanoelectromechanical resonators (GrNEMS), known also as graphene nanodrums or nanomembranes. We demonstrate that these devices,…
Generalized Hamiltonian for Kekulé graphene and the emergence of valley-cooperative Klein tunneling
Santiago Galván y García, Thomas Stegmann, Yonatan Betancur-Ocampo
We introduce a generalized Hamiltonian describing not only all topological phases observed experimentally in Kekulé graphene (KekGr) but predicting also new ones. These phases show…
Valley-dependent time evolution of coherent electron states in tilted anisotropic Dirac materials
Yonatan Betancur-Ocampo, Erik Díaz-Bautista, Thomas Stegmann
The effect of the Dirac cone tilt of anisotropic two-dimensional materials on the time evolution of coherent electron states in the presence of electric and magnetic fields is stud…
Steering the current flow in twisted bilayer graphene
Jesús Arturo Sánchez-Sánchez, Montserrat Navarro-Espino, Yonatan Betancur-Ocampo +2
A nanoelectronic device made of twisted bilayer graphene (TBLG) is proposed to steer the direction of the current flow. The ballistic electron current, injected at one edge of the…
Anomalous Floquet tunneling in uniaxially strained graphene
Yonatan Betancur-Ocampo, Parisa Majari, Diego Espitia +2
The interplay of strain engineering and photon-assisted tunneling of electrons in graphene is considered for giving rise to atypical transport phenomena. The combination of uniaxia…
Gradient-index electron optics in graphene pn junctions
Emmanuel Paredes-Rocha, Yonatan Betancur-Ocampo, Nikodem Szpak +1
We investigate the electron transport in smooth graphene pn junctions, generated by gradually varying electrostatic potentials. The numerically calculated coherent current flow pat…
Phosphorene pnp junctions as perfect electron waveguides
Yonatan Betancur-Ocampo, Emmanuel Paredes-Rocha, Thomas Stegmann
The current flow in phosphorene pnp junctions is studied. At the interfaces of the junction, omni-directional total reflection takes place, named anti-super-Klein tunneling, as thi…
Current vortices in aromatic carbon molecules
Thomas Stegmann, John A. Franco-Villafañe, Yenni P. Ortiz +6
The local current flow through three small aromatic carbon molecules, namely benzene, naphthalene and anthracene, is studied. Applying density functional theory and the non-equilib…
Electron optics in phosphorene pn junctions: Negative reflection and anti super-Klein tunneling
Yonatan Betancur-Ocampo, François Leyvraz, Thomas Stegmann
Ballistic electrons in phosphorene junctions show optical-like phenomena. Phosphorene is modeled by a tight-binding Hamiltonian that describes its electronic structure at low…
Current splitting and valley polarization in elastically deformed graphene
Thomas Stegmann, Nikodem Szpak
Elastic deformations of graphene can significantly change the flow paths and valley polarization of the electric currents. We investigate these phenomena in graphene nanoribbons wi…
Nonequilibrium distribution functions in electron transport: Decoherence, energy redistribution and dissipation
Thomas Stegmann, Orsolya Ujsághy, Dietrich E. Wolf
A new statistical model for the combined effects of decoherence, energy redistribution and dissipation on electron transport in large quantum systems is introduced. The essential i…
Transport gap engineering by contact geometry in graphene nanoribbons: Experimental and theoretical studies on artificial materials
Thomas Stegmann, John A. Franco-Villafañe, Ulrich Kuhl +2
Electron transport in small graphene nanoribbons is studied by microwave emulation experiments and tight-binding calculations. In particular, it is investigated under which conditi…
Microwave emulations and tight-binding calculations of transport in polyacetylene
Thomas Stegmann, John A. Franco-Villafañe, Yenni P. Ortiz +3
A novel approach to investigate the electron transport of cis- and trans-polyacetylene chains in the single-electron approximation is presented by using microwave emulation measure…
Current flow paths in deformed graphene: from quantum transport to classical trajectories in curved space
Thomas Stegmann, Nikodem Szpak
In this work we compare two fundamentally different approaches to the electronic transport in deformed graphene: a) the condensed matter approach in which current flow paths are ob…
Edge magnetotransport in graphene: A combined analytical and numerical study
Thomas Stegmann, Axel Lorke
The current flow along the boundary of graphene stripes in a perpendicular magnetic field is studied theoretically by the nonequilibrium Green's function method. In the case of spe…
Magnetotransport along a boundary: From coherent electron focusing to edge channel transport
Thomas Stegmann, Dietrich E. Wolf, Axel Lorke
We study theoretically how electrons, coherently injected at one point on the boundary of a two-dimensional electron system, are focused by a perpendicular magnetic field onto…
Statistical model for the effects of phase and momentum randomization on electron transport
Thomas Stegmann, Matías Zilly, Orsolya Ujsághy +1
A simple statistical model for the effects of dephasing on electron transport in one-dimensional quantum systems is introduced, which allows to adjust the degree of phase and momen…