We report the effect of linear absorption on self-focusing. Our experimental results show that power loss due to linear absorption before focus is responsible for the increase in the threshold power for self-focusing and that the critical power is independent of the linear absorption.

In this paper, a spectroscopic sensor formed by a silicon-on-insulator waveguiding Bragg grating ring resonator working in linear and non-linear regime is proposed. In linear regime, the device shows a spectral response characterized by a photonic band gap (PBG). Very close to the band gap edges, the resonant structure exhibits split modes having a splitting magnitude equal to the PBG spectral ...

The evolution of the electronic absorption edge of type I, II and III kerogen is studied by diffuse reflectance UV–Visible absorption spectroscopy. The functional form of the electronic absorption edge for all kerogens measured is in excellent agreement with the ‘‘Urbach tail’’ phenomenology. The Urbach decay width extracted from the exponential fit within the visible range is strongly correlat...

We have expressed the nonlinear optical absorption of a semiconductor in terms of its linear spectrum. We determined that the two-photon absorption coefficient in a strong DCelectric field of a direct gap semiconductor can be expressed as the product of a differential operator times the convolution integral of the linear absorption without a DC-electric field and an Airy function. We have appli...

This paper investigated the moisture absorption, mechanical behavior and the dielectric performance of hybrid and non-hybrid polymeric composites. Hand lay-up technique was used for processing carbon; glass reinforced polyester resin composites (non-hybrid) and carbon-glass/polyester hybrid composites with various fiber configurations. The maximum resistance of water absorption was obtained for...

Terahertz metasurfaces with pixelated meta-atoms were designed for linear-polarization conversion and absorption. The differences between the two functionalities emerged from number arrangement of metal-dielectric combos patching some but not necessarily every pixel each meta-atom. A a meta-atom 3×3 pixels yielded polarization ratio (PCR) >0.9 over 10.20–16.08 THz band, whereas another absorpta...