Related papers: A controllable valley polarization in Graphene
We derive the angular generation density of photoexcited carriers in gapless and gapped Bernal bilayer graphene. Exploiting the strong anisotropy of the band structure of bilayer graphene at low energies due to trigonal warping, we show…
Twisted bilayer graphene (TBG) aligned with hexagonal boron nitride (h-BN) substrate can exhibit an anomalous Hall effect at 3/4 filling due to the spontaneous valley polarization in valley resolved moir\'e bands with opposite Chern number…
We theoretically study the transmittance for normal incidence of linearly polarized light between two media separated by a strained graphene monolayer. We analytically characterize the degree of dichroism and the transparency of graphene as…
The electron transmission between monolayer and bilayer graphene is theoretically studied for zigzag and armchair boundaries within an effective-mass scheme. Due to the presence of an evanescent wave in the bilayer graphene, traveling modes…
The altermagnetism caused by alternating crystal environment provides a unique opportunity for designing new type of valley polarization. Here, we propose a way to realize valley polarization in two-dimensional (2D) tetragonal…
In solid, the crystalline structure can endow electron an internal degree of freedom known as valley, which characterizes the degenerate energy minima in momentum space. The recent success in optical pumping of valley polarization in 2D…
The modulation of the optical transmittance in multilayer graphene by means of an electrical signal in the simple configuration of coplanar electrodes is reported. Besides the fundamental frequency of modulation, higher harmonics also…
Valley polarization (VP), an induced imbalance in the populations of a multi-valley electronic system, allows emission of second harmonic (SH) light even in centrosymmetric crystals such as graphene. Whereas in systems such as…
Measuring degeneracy and broken-symmetry states of a system at nanoscale requires extremely high energy and spatial resolution, which has so far eluded direct observation. Here, we realize measurement of the degeneracy and subtle…
We study electron transport properties of a monoatomic graphite layer (graphene) with different types of disorder at half filling. We show that the transport properties of the system depend strongly on the symmetry of disorder. We find that…
Realistic relaxed configurations of triaxially strained graphene quantum dots are obtained from unbiased atomistic mechanical simulations. The local electronic structure and quantum transport characteristics of y-junctions based on such…
This work investigates the feasibility of electrical valley filtering for holes in transition metal dichalcogenides. We look specifically into the scheme that utilizes a potential barrier to produce valley-dependent tunneling rates, and…
We theoretically investigate the interaction of an ultrastrong femtosecond-long linearly polarized optical pulse with AB-stacked bilayer graphene. The pulse excite electrons from the valence into the conduction band, resulting in finite…
We test the valley-filtering capabilities of a quantum dot inscribed by locally straining an $\alpha$-$\mathcal{T}_3$ lattice. Specifically, we consider an out-of-plane Gaussian bump in the center of a four-terminal configuration and…
When passing an optical medium in the presence of a magnetic field, the polarization of light can be rotated either when reflected at the surface (Kerr effect) or when transmitted through the material (Faraday rotation). This phenomenon is…
An atomic carbon chain joining two graphene flakes was recently realized in a ground-breaking experiment by Jin {\it et al.}, Phys. Rev. Lett. {\bf 102}, 205501 (2009). We present {\it ab initio} results for the electron transport…
Exerting well-defined control over the reflection $(R)$, absorption $(A)$, and transmission $(T)$ of electromagnetic waves is a key objective in quantum optics. To this end, one often utilizes hybrid structures comprised of elements with…
We study low-frequency linearly-polarized laser-dressing in materials with valley (graphene and hexagonal-Boron-Nitride), and topological (Dirac- and Weyl-semimetals), properties. In Dirac-like linearly-dispersing bands, the laser…
Bilayer graphene hosts valley-chiral one dimensional modes at domain walls between regions of different interlayer potential or stacking order. When such a channel is brought into proximity to a superconductor, the two electrons of a Cooper…
We investigate the electron transport in smooth graphene pn junctions, generated by gradually varying electrostatic potentials. The numerically calculated coherent current flow patterns can be understood largely in terms of semi-classical…