Wavefront correction and customization of focal spot of 100TW Ti : sapphire laser system

Abstract

The measurement and correction of wavefront aberrations of the 100TW Ti:sapphire laser beam are presented. Several monochromatic aberrations, such as astigmatism (Z(2)(-2), Z(2)(2)), coma (Z(3)(-1)), trefoil (Z(3)(-3), Z(3)(3)), and spherical aberration (Z(4)(0)) are observed in the 100TW Ti:sapphire laser beam as well as defocus (Z(2)(0)), which is responsible for the converging or diverging of a laser pulse. An adaptive optics system using a bimorph deformable mirror successfully corrected a monochromatic wavefront in the 100TW Ti:sapphire laser beam. The customization of the focal spot is also investigated using the adaptive optics system for research on the efficient generation of a high- energy electron beam. The increase in the depth of focus is demonstrated and the temporal broadening is calculated when the spherical aberration is introduced using the adaptive optics system.