Related papers: Control of excitonic absorption by thickness varia…
We present first-principles calculations of many-electron effects on the optical response of graphene, bilayer graphene, and graphite employing the GW-Bethe Salpeter equation approach. We find that resonant excitons are formed in these…
The positive effects of various perturbations introduced in a bidimensional photonic-crystal patterned membrane on its integrated absorption are investigated numerically and theoretically. Two phenomena responsible for the enhanced…
The impressive physics and applications of intra- and interlayer excitons in a transition metal dichalcogenide twisted-bilayer make these systems compelling platforms for exploring the manipulation of their optoelectronic properties through…
The improvement of light absorption in Si/BeSe$_{0.41}$Te$_{0.59}$ heterostructures for solar cell applications is studied theoretically. First, using simple approaches we found that light absorption could be improved in a single…
We perform linear and non-linear photon absorption calculations in topological insulator ultra-thin films on a substrate. Due to the unique band structure of the coupled topological surface states, novel features are observed for suitable…
The energy position of the optical absorption edge and the free carrier populations in InxGa1-xN ternary alloys can be controlled using high energy 4He+ irradiation. The blue shift of the absorption edge after irradiation in In-rich…
Optical vortices (OVs) have rapidly varying spatial phase and optical energy that circulates around points or lines of zero optical intensity. Manipulation of OV offers innovative approaches for various fields, such as optical sensing,…
Molecular adsorption is pivotal in device fabrication and material synthesis for quantum technology. However, elucidating the behavior of physisorption poses technical challenges. Here graphene with ultrahigh sensitivity was utilized to…
The formation of excitonic insulator phases in quantum materials is often masked by structural distortions caused by the coupling between electronic and phononic order parameters. Here we show that the candidate material Ta$_2$NiSe$_5$ is…
The advance in designing arrays of ultrathin two-dimensional optical nano-resonators, known as metasurfaces, is currently enabling a large variety of novel flat optical components. The remarkable control over the electromagnetic fields…
Deterministic control of excitonic properties is key to advancing nanoscale optoelectronic and quantum technologies and to understanding diverse physical, optical, chemical, and biological phenomena. At the molecular scale, these properties…
Atomic-scale control of light-matter interactions represent the ultimate frontier for many applications in photonics and quantum technology. Two-dimensional semiconductors, including transition metal dichalcogenides, are a promising…
Two approaches (micro- and macro- investigations) are used to determine the dimension dependences of the optical parameters of the nanometer-scale layers of materials. It is shown that both an index of refraction and coefficient of…
We investigate the excitonic spectrum of MoS$_2$ monolayers and calculate its optical absorption properties over a wide range of energies. Our approach takes into account the anomalous screening in two dimensions and the presence of a…
We report the infrared transmission measurement on electrically gated twisted bilayer graphene. The optical absorption spectrum clearly manifests the dramatic changes such as the splitting of inter-linear-band absorption step, the shift of…
Optical gain is a critical process in today's semiconductor technology and it is most often achieved via stimulated emission. In this theoretical study, we find a resonant TE mode in biased low-symmetry two-dimensional metallic systems…
We calculate, as a function of temperature and conduction band electron density, the optical absorption of a weakly n-doped, idealized semiconductor quantum well. In particular, we focus on the absorption band due to the formation of a…
When a semiconductor absorbs light, the resulting electron-hole superposition amounts to a uncontrolled quantum ripple that eventually degenerates into diffusion. If the conformation of these excitonic superpositions could be engineered,…
An ab initio approach to the calculation of excitonic effects in the optical absorption spectra of semiconductors and insulators is formulated. It starts from a quasiparticle bandstructure calculation and is based on the relevant…
The optical absorption properties of graphene wrapped dielectric particles have been investigated by using Mie scattering theory and exact multi-scattering method. It is shown that subwavelength strong absorption in infrared spectra can…