相关论文: Strong-Field Bloch Electron Interferometry for Ban…
In solid state conductors, linear response to a steady electric field is normally dominated by Bloch state occupation number changes that are correlated with group velocity and lead to a steady state current. However, for a number of…
Scanning tunneling spectroscopy (STS) has yielded significant insight on the electronic structure of graphene and other two-dimensional (2D) materials. STS directly measures a fundamental and directly calculable quantity: the single…
The 1+1 layer folded graphene sheets that deviate from AB stacking are successfully fabricated and their electronic structures are investigated by Raman spectroscopy. Significant blue shift of the 2D band of folded graphene compared to that…
Inspired by recent experiments with cold atoms in optical lattices, we consider a St\"uckelberg interferometer for a particle performing Bloch oscillations in a tight-binding model on the honeycomb lattice. The interferometer is made of two…
Dispersionless energy bands are a peculiar property gathering increasing attention for the emergence of novel photonic, magnetic and electronic properties. Here we report the first observation of a graphene superstructure n-doped up to the…
We describe a technique which allows a direct measurement of the relative Fermi energy in an electron system using a double layer structure, where graphene is one of the two layers. We illustrate this method by probing the Fermi energy as a…
Exploiting high-energy electron beams colliding into high-intensity laser pulses brings an opportunity to reach high values of the dimensionless rest-frame acceleration $\chi$ and thereby invoke processes described by strong-field quantum…
The absence of a well-defined Fermi surface in flat-band systems challenges the conventional understanding of instabilities toward Landau order based on nesting. We investigate the existence of an intrinsic nesting structure encoded in the…
The electronic structures of the ferromagnetic superconductors $\mathrm{UGe}_2$ and $\mathrm{UCoGe}$ in the paramagnetic phase were studied by angle-resolved photoelectron spectroscopy using soft X-rays ($h\nu =400-500$). The quasi-particle…
We review recent experimental results indicating the band flattening and Landau level merging at the chemical potential in strongly-correlated two-dimensional (2D) electron systems. In ultra-clean, strongly interacting 2D electron system in…
We propose an all-optical method to directly reconstruct the band structure of semiconductors. Our scheme is based on the temporal Young's interferometer realized by high harmonic generation (HHG) with a few-cycle laser pulse. As a…
It is demonstrated that itinerant-localized transition of heavy electrons occurs inside the magnetically ordered phase of the Kondo-Heisenberg lattice. The phase diagram and electronic structure are derived by means of the continuous-time…
Flat-band materials have attracted substantial interest for their intriguing quantum geometric effects. Here we investigate how singular flat bands (SFBs) respond to a static, uniform electric field and whether they can support…
The magnetoelectronic properties of quasi-one-dimensional zigzag graphene nanoribbons are investigated by using the Peierls tight-binding model. Quasi-Landau levels (QLLs), dispersionless Landau subbands within a certain region of k-space,…
We present infrared spectra (0.1-1 eV) of electrostatically gated bilayer graphene as a function of doping and compare it with tight binding calculations. All major spectral features corresponding to the expected interband transitions are…
A systematic review is made for the AA-, AB- and ABC-stacked graphites. The generalized tight-binding model, accompanied with the effective-mass approximation and the Kubo formula, is developed to investigate electronic and optical…
frared reflectance spectroscopy at 4K in fields up to 31T. Both Schr\"odinger-like (K-point) and Dirac-like (H-point) Landau level transitions have been observed, and their magnetic field dispersion are analyzed by a newly-derived limiting…
The nature of relativistic electrons in solids depends on the precise shape of the underlying band structure. Prominently, symmetry-related mechanisms, such as the breaking of time reversal symmetry in topological insulators, can lead to…
We consider a multiband metal with deep primary bands and a shallow secondary one. In the normal state the system undergoes Lifshitz transition when the bottom of the shallow band crosses the Fermi level. In the superconducting state Cooper…
The emerging possibilities to steer and control electronic motion on subcycle time scales with strong electric fields enable studying the nonperturbative optical response and Bloch bands' topological properties, originated from Berry's…