الفهرس 
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Abstract
This thesis focused on studying nonlinear optical properties of materials and its applications. Nonlinear refractive index and nonlinear absorption coefficient of soda-lime glass and indium tin oxide thin film were studied and measured using z-scan technique. The study was done over abroad range of wavelengths from 720 nm to 900 nm and excitation intensities ranging from 58 GW/cm2 to 182 GW/cm2 using femtosecond laser pulses with high repetition rate 80 MHz.
The obtained results showed saturated three photon absorption (3PA) for soda-lime glass, while ITO thin film has two photon absorption (2PA) with combination of saturable and reverse saturable absorption behaviors. Nonlinear refractive index measurements exhibit positive nonlinear refractive index for both soda-lime and ITO thin film. ITO thin film has large nonlinear refractive index 104 times that of soda-lime glass. The thermal lens effect has been treated by using a new method which was developed to consider the accumulative thermal lensing in the sample due to the high repetition rate fs laser pulses.
The experimental results using z-scan technique combined with detecting of laser pulses transmitted from the sample showed no optical limiting response for soda-lime glass and ITO thin film in the wavelengths range from 750 nm to 1000 nm. This is mainly because the materials showed saturable absorption behavior.
The self-compression of femtosecond laser pulses was studied and evaluated numerically taken into account the interplay between group velocity dispersion (GVD) and self-phase modulation (SPM). The compression study occurred at different soda-lime thickness. A numerical simulation of the transmission of a 200fs laser pulse through soda-lime glass of 1.2cm thickness showed that the interplay between anomalous GVD and SPM lead to a significant compression of the pulse to 8.5 fs i.e., by a compression factor of 23.