Petawatt-class laser optimization and ultrashort probe pulse generation for relativistic laser-plasma interactions

Advancements in high peak power laser development have resulted in laser systems capable of accelerating charged particles in a plasma to nearly the speed of light. For a comprehensive understanding and optimization of such interactions towards higher experimental yields, further enhancements in the laser system performance are required, along with a method that enables a direct view into the laser-induced plasma with a high spatial and temporal resolution. The work presented in this thesis details the results of multiple investigations regarding upgrades to the petawatt-class POLARIS laser and the development of a multi-beam ultrashort laser system for probing relativistic laser-plasma interactions at Friedrich Schiller University and Helmholtz Institute in Jena, Germany.