Multiband tunneling in trilayer graphene

Abstract

The electronic tunneling properties of the two stable forms of trilayer graphene (TLG), rhombohedral ABC and Bernal ABA, are examined for pn and pnp junctions as realized by using a single gate (SG) or a double gate (DG). For the rhombohedral form, due to the chirality of the electrons, the Klein paradox is found at normal incidence for SG devices while at high energy interband scattering between additional propagation modes can occur. The electrons in Bernal ABA TLG can have a monolayer-or bilayer-like character when incident on a SG device. Using a DG however both propagation modes will couple by breaking the mirror symmetry of the system which induces intermode scattering and resonances that depend on the width of the DG pnp junction. For ABC TLG the DG opens up a band gap which suppresses Klein tunneling. The DG induces also an unexpected asymmetry in the tunneling angle for single valley electrons.

Goos–Hänchen shifts in AA-stacked bilayer graphene superlattices

“…Plots of the energy bands structure in AA-stacked BLG, evaluating (5) for the barrier region, have been shown in Figure 3. We clearly see that the energy bands are different from that of the AB-stacked BLG [27] and also monolayer graphene [1]. One can observe that for zero gap, the energy bands are linear and just two copies of the monolayer band structure shifted up and down by γ = 0.2 eV (Figure 3(a)), respectively.…”

“…It may be noted that for AB-stacked BLG, in the four band model, we have four reflection and four transmission channels [27]. For AA-stacked BLG, all intercone transitions (τ −→ −τ ) are strictly forbidden due to the orthogonality of electron wave functions with a different cone index [28], which yield to only two transmissions (τ −→ τ ).…”

“…Our transmission for the upper layer T + is equal to the transmission for the lower layer T − , which give the total transmission as average. Recall that, for AB-stacked BLG the total transmission is resulting from four transmission channels [27].…”

Creating in-plane pseudomagnetic fields in excess of 1000 T by misoriented stacking in a graphene bilayer

“…, where the subscript 1 and 2 enumerate the layers [24,47]. By written shown in Figure 4(b), depends sensitively on the in-plane magnetic field.…”

Ballistic electron propagation through periodic few-layer graphene nanostructures

“…[20] and [21]; the case of mono-and bilayer graphene superlattices is treated in [22]. The transmission of chiral charge carriers through potential barriers in trilayer graphene has been discussed in [23,24].…”