相关论文: Infrared spectroscopy of electronic bands in bilay…
It is well known that a direct band gap may be opened in bilayer graphene via the application of a perpendicular electric field (bias). The bias and the chemical potential are controlled by electrostatic gating where the top and bottom gate…
Using the tight-binding model, we report a gap opening in the energy spectrum of the twisted bilayer graphene under the application of pressure, that can be further amplified by the presence of a perpendicular bias voltage. The valley edges…
Few-layer graphene possesses low-energy carriers which behave as massive fermions, exhibiting intriguing properties in both transport and light scattering experiments. Lowering the excitation energy of resonance Raman spectroscopy down to…
Bilayer graphene (BLG) possesses a finite bandgap when a potential difference is introduced between the two graphene layers. The potential difference is known to be introduced by surface charge transfer. Thus, it is expected that a finite…
We investigate theoretically the interplay between the effects of a perpendicular electric field and incommensurability at the interface on the electronic properties of a heterostructure of bilayer graphene and a semiconducting substrate…
Recent measurements have shown that a continuously tunable bandgap of up to 250 meV can be generated in biased bilayer graphene [Y. Zhang et al., Nature 459, 820 (2009)], opening up pathway for possible graphene-based nanoelectronic and…
We present transport measurements on a bilayer graphene sheet with homogeneous back gate and split top gate. The electronic transport data indicates the capability to direct electron flow through graphene nanostructures purely defined by…
The salient property of the electronic band structure of twisted bilayer graphene (TBG), at the so-called magic angle (MA), is the emergence of flat bands around the charge neutrality point. These bands are associated with the observed…
The unusual transport properties of graphene are the direct consequence of a peculiar bandstructure near the Dirac point. We determine the shape of the pi bands and their characteristic splitting, and the transition from a pure 2D to…
We show that gated bilayer graphene zigzag ribbons possess a fast and a slow edge, characterized by edge state velocities that differ due to non-negligible next-nearest-neighbor hopping elements. By applying bosonization and renormalization…
While the exponential decay of tunneling probability with barrier thickness is well known, the accompanying oscillations with thickness have been comparatively less explored. Using a tight binding model, we investigate an AB-stacked bilayer…
We have investigated the effects of inplane and interplane nearest neighbour overlap integrals ($s_0$ and $s_1$) and site energy difference between atoms in two different sublattices in the same graphene layer ($\Delta$) on the electronic…
We present atomistic calculations on structural and electronic properties of twisted double bilayer graphene (TDBG) consisting of two sets of rotationally misaligned Bernal-stacked bilayer graphene. Obtained equilibrium atomic structures…
The potential of graphene-based materials consisting of one or a few layers of graphite for integrated electronics originates from the large room-temperature carrier mobility in these systems (approx. 10,000 cm2/Vs). However, the…
We investigate the electronic structure of alternating-twist triple Bernal-stacked bilayer graphene (t3BG) as a function of interlayer coupling $\omega$, twist angle $\theta$, interlayer potential difference $\Delta$, and top-bottom…
Marginally twisted bilayer graphene having small twist angles is predicted to exhibit unique structural and electronic properties, though experimental characterization remains limited. Using scanning tunneling microscopy, we investigate…
We report phonon renormalisation in bilayer graphene as a function of doping. The Raman G peak stiffens and sharpens for both electron and hole doping, as a result of the non-adiabatic Kohn anomaly at the $\Gamma$ point. The bilayer has two…
Bilayer graphene has drawn significant attention due to the opening of a band gap in its low energy electronic spectrum, which offers a promising route to electronic applications. The gap can be either tunable through an external electric…
We present a systematic Raman study of unconventionally-stacked double-layer graphene, and find that the spectrum strongly depends on the relative rotation angle between layers. Rotation-dependent trends in the position, width and intensity…
A remarkable feature of the band structure of bilayer graphene at small twist angle is the appearance of isolated bands near neutrality, whose bandwidth can be reduced at certain magic angles (eg. $\theta\sim 1.05^\circ$). In this regime,…