Related papers: Control of excitonic absorption by thickness varia…
Dynamical control of the nonlinear optical properties of solids -- with light itself -- will be essential for future ultrafast photonic technologies. Previously, methods to modulate nonlinear processes including second-harmonic generation…
An excitonic insulator (EI) phase is a consequence of collective many-body effects where an optical band gap is formed by the condensation of electron-hole pairs or excitons. We report pressure-dependent optical pump optical probe…
Applying the novel exact-exchange (EXX) Kohn-Sham method within time-dependent density-functional theory, we obtained the optical absorption spectrum of bulk silicon in good agreement with experiments including excitonic features. Analysis…
The coherent interaction of light with matter imprints the phase information of the light field on the wavefunction of the photon-dressed electronic state. Driving electric field, together with a stable phase that is associated with the…
Nanoscale strain control of exciton funneling is an increasingly critical tool for the scalable production of single photon emitters (SPEs) in two-dimensional materials. However, conventional far-field optical microscopies remain…
We report mid-infrared spectroscopy measurements of an electrostatically gated topological insulator, in which we observe several percent modulation of transmittance and reflectance of (Bi1-xSbx)2Te3 films as gating shifts the Fermi level.…
${\gamma}$-GeSe is a new type of layered bulk material that was recently successfully synthesized. By means of density functional theory first-principles calculations, we systematically studied the physical properties of two-dimensional…
Monolayers of transition metal dichalcogenides (TMDCs) have emerged as new optoelectronic materials in the two dimensional (2D) limit, exhibiting rich spin-valley interplays, tunable excitonic effects, and strong light-matter interactions.…
Engineering and probing excitonic properties at the nanoscale remains a central challenge in quantum photonics and optoelectronics. While exciton confinement via electrical control and strain engineering has been demonstrated in 2D…
We present ab initio many-body calculations of the optical absorption in bulk graphite, graphene and bilayer of graphene. Electron-hole interaction is included solving the Bethe-Salpeter equation on top of a GW quasiparticle electronic…
By exploiting singular spatial modulations of the graphene conductivity, we design a broadband, tunable THz absorber whose efficiency approaches the theoretical upper bound for a wide absorption band with a fractional bandwidth of 185\%.…
We propose a method to reconstruct the density of an optical source in a highly scattering medium from ultrasound-modulated optical measurements. Our approach is based on the solution to a hybrid inverse source problem for the radiative…
Opals are naturally occurring photonic crystals which can be formed easily using low-cost self-assembly methods. While the optical behaviour of opals has received significant attention over the last number of decades, there is limited…
An electro-absorption optical modulator concept based upon a dual-graphene layer is presented. The device consists of a silicon-on-insulator waveguide upon which two graphene layers reside, separated by a thin insulating region. The lower…
We explore the coherent control of nonlinear absorption of intense laser fields in four-level atomic systems. For instance, in a four-level ladder system, a coupling field creates electromagnetically induced transparency (EIT) with…
Using first principles many-body theory methods (GW+BSE) we demonstrate that optical properties of graphane are dominated by localized charge-transfer excitations governed by enhanced electron correlations in a two-dimensional dielectric…
The quasiparticle band structure and optical properties of single-walled zigzag and armchair SiC nanotubes (SiC-NTs) as well as single SiC sheet are investigated by ab initio many-body calculations using the GW and the GW plus…
Control over intensity, shape, direction, and phase of coherent light is essential in numerous fields, reaching from gravitational wave astronomy over quantum metrology and ultrafast sciences to semi-conductor fabrication. Modern laser…
We report the experimental observation of all-optical modulation of light in a graphene film. The graphene film is scanned across a standing wave formed by two counter-propagating laser beams in a Sagnac interferometer. Through a coherent…
Microscopy and optical imaging are drastically limited by the inhomogeneities encountered by the light while propagating from the object of interest to the detection system. In this context, adaptive optics and wavefront manipulation are…