Related papers: Reflectivity spectra as absorption ones -- is it c…
Omni-resonance refers to the broadening of the spectral transmission through a planar cavity, not by changing the cavity structure, but by judiciously preconditioning the incident optical field. As such, broadband imaging can be performed…
Relativistic reflection features are commonly observed in the X-ray spectra of accreting black holes. In the presence of high quality data and with the correct astrophysical model, X-ray reflection spectroscopy can be quite a powerful tool…
Rigourous calculations of the imaging properties of metamaterials consisting of metal-coated semiconductor nanoparticles are presented. In particular, it is shown that under proper choice of geometric and materials parameters, arrays of…
With analytical (generalized Mie scattering) and numerical (integral-equation-based) considerations we show the existence of strong resonances in the scattering response of small spheres with lossless impedance boundary. With increasing…
At radio wavelengths, scattering in the interstellar medium distorts the appearance of astronomical sources. Averaged over a scattering ensemble, the result is a blurred image of the source. However, Narayan & Goodman (1989) and Goodman &…
The scattering of quasiperiodic waves for a two-dimensional Helmholtz equation with a constant refractive index perturbed by a function which is periodic in one direction and of finite support in the other is considered. The scattering…
Metasurface based super absorbers exhibit near unity absorbance. While the absorption peak can be tuned by the geometry/size of the sub-wavelength resonator, broadband absorption can be obtained by placing multiple resonators of various…
Ray tracing is widely employed to model the propagation of radio-frequency (RF) signal in complex environment. The modelling performance greatly depends on how accurately the target scene can be depicted, including the scene geometry and…
The backward scattering of TM-polarized light by a two-side-open subwavelength slit in a metal film is analyzed. We show that the reflection coefficient versus wavelength possesses a Fabry-Perot-like dependence that is similar to the…
X-ray reflection generates much of the spectral complexity in the X-ray spectra of AGN. It is argued that strong relativistic blurring of the reflection spectrum should commonly be expected from objects accreting at a high Eddington rate.…
We find a new set of exact solutions to Maxwell's equations in space--time varying materials, where the refractive index is constant, while the impedance exhibits effective motion, i.e. it is a function of $x-vt$. We find that waves…
We consider a semi-infinite spatially dispersive dielectric with unequal transverse and longitudinal susceptibilities. The effect of the boundary is characterized by arbitrary reflection coefficients for polarization waves in the material…
Black materials play a critical role in applications such as image registration, camera calibration, stray light suppression, and visual design. Although many such materials appear similarly dark under diffuse illumination, their…
Doppler reflectometry spatial and wavenumber resolution is analyzed within the framework of the linear Born approximation in slab plasma model. Explicit expression for its signal backscattering spectrum is obtained in terms of wavenumber…
The determination of density profiles with knowing the phase information of complex reflection coefficient for neutron specularly reflected from a film, yields unique results. Recently it has been shown that the phase can be determined by…
X-ray reflection signatures are observed around multiple classes of accreting compact objects. Modelling these features yield important constraints on the physics of accretion disks, motivating the development of X-ray reflection models…
We study the mode conversion and resonant absorption phenomena occurring in a slab of a stratified anisotropic medium, optical axes of which are tilted with respect to the direction of inhomogeneity, using the invariant imbedding theory of…
We report the visible reflection spectrum of the integrated Earth, illuminated as it would be seen as an spatially-unresolved extrasolar planet. The spectrum was derived from observation of lunar earthshine in the range 4800 to 9200…
A key optical parameter characterizing the existence of negative refraction in a thin layer of a composite material is the effective refractive index of an equivalent, homogenized layer with the same physical thickness as the initial…
We develop a quantitative description of giant asymmetry in reflectance, recently observed in semicontinuous metal films. The developed scaling-theory based technique reproduces the spectral properties of semicontinuous composites, as well…