Laser amplifiers is a field of study concerned with the principles, design, and optimization of devices that increase the power or energy of coherent light (laser beams) through the process of stimulated emission. This research area investigates the physics of gain media, pumping mechanisms, energy extraction dynamics, and optical propagation effects necessary for achieving high gain, efficiency, and output power while preserving beam quality. The development of effective laser amplifiers is crucial for enabling high-intensity laser systems utilized in diverse applications including inertial confinement fusion, advanced manufacturing, scientific research, and medical procedures.