We investigate nonanalyticities (e.g., zeros and poles) of refractive index $n(\ensuremath{\omega})$ group ${n}_{g}(\ensuremath{\omega})$ in different optical media. first demonstrate that while a Lorentzian dielectric has no nonanalyticity the upper half complex frequency plane (CFP), its index---which governs pulse-center propagation---possesses same region. Thus we classify as (a) order (ref...

Silicon thin layers are deposited on glass substrates with the thickness of 103 nm, 147 nm and 197 nm. The layers are produced with electron gun evaporation method under ultra-high vacuum condition. The optical Reectance and the Transmittance of produced layers were measured by using spectrophotometer. The optical functions such as, real and imaginary part of refractive index, real and imaginar...

We present experimental results of the transmission magnitude and phase change of terahertz pulses through thin metallic films patterned with subwavelength hole arrays on silicon wafers. Terahertz time-domain spectroscopy measurements reveal a sharp phase peak centered on the surface plasmon resonance. Correspondingly, and consistent with the Kramers-Kronig relations, the measured transmission ...

The influence of strong loss peaks on the dispersion (through the Kramers-Kronig relations) of a nonlinear waveguide is investigated theoretically. It is found specifically for degenerate four-wave mixing in a poly(methyl methacrylate) microstructured polymer optical fiber that the loss-induced dispersion significantly modifies the wavelengths for which there is phase-match. Depending on the pu...

2014 Normal and oblique incidence reflectances of GaTe have been measured in the 2.5 to 26 eV range using polarized synchrotron radiation. We have deduced 3 complex refractive indices, relative to 3 different crystallographic directions by means of a new method consistent with the Kramers-Kronig relations. We have verified that the electronic transitions in the 20 eV region, from the 3d Ga leve...

Mesoporous layers of silica are of interest for many optical applications, including the creation of devices ranging from optical sensors to laser sources with promising characteristics. Their optical characterization goes through the interpretation of measurements. We propose to give experimental results of reflectance and scattering measurements concerning mesoporous layers of silica deposite...

The contribution of ions to the electrical impedance of an electrolytic cell limited by perfect blocking electrodes is determined by considering the role of the anomalous diffusion process and memory effects. Analytical solutions for fractional diffusion equations together with Poisson's equation relating the effective electric field to the net charge density are found. This procedure allows th...