Characteristics of KrF-Excimer-Laser Induced Absorption in Synthetic Fused Silica: Relation Between Intensities of Induced Absorption and Internal Absorption at 200nm.

Mechanisms of absorption in pulsed excimer laser-induced plasma

This work investigates the interaction between pulsed excimer laser-induced plasma and an excimer laser beam. The optical transmissivity through the laser-induced plasma and the velocity of the plasma front are measured within the duration of the laser pulse. Based on the measured velocity of the plasma front, an analysis of compressible gas dynamics is used to compute the thermodynamic propert...

Femtosecond laser absorption in fused silica: Numerical and experimental investigation

Single pulse transmissivity and reflectivity of fused silica irradiated by tightly focused 90 fs laser pulses at a center wavelength of 800 nm are numerically and experimentally investigated to study the role of nonlinear photoionization and avalanche ionization processes in free electron generation. The laser beam inside fused silica is modeled with a 2+1 -dimensional propagation equation whic...

Controlling of Absorption and Dispersion Spectrum via Electromagnetically Induced Transparency

In this paper we examine the absorption and dispersion properties of a weak probe field via Electromagnetically Induced Transparency (EIT) in a four-level system. It is shown that under certain condition, using this model, the absorption cancellation is appeared and the medium becomes transparent to the weak probe field. It will be shown that the controlling of absorption and dispersion spectru...

The effect of self-absorption correction using internal reference on determining heavy metals concentration by laser induced breakdown spectroscopy

The identification and concentration of heavy metals, which may be so harmful for the body, is determined by the method of calibration-free laser-induced breakdown spectroscopy using a special strategy. First, the plasma temperature is obtained using the Boltzmann plot. Then, a line with an inappreciable self-absorption is considered for each element as the reference. The modified intensities o...

Dynamics of femtosecond laser absorption of fused silica in the ablation regime