A controllable laser amplifier apparatus includes a gain medium and a seed laser emitter configured to generate a seed laser beam, the seed laser emitter directed toward the gain medium. The apparatus has at least two pump laser emitters configured to generate respective pump laser beams, wherein the pump laser emitters are adjustable such that respective intensities of the pump laser beams are adjustable relative to one another and/or relative to the seed laser pump, wherein the pump laser emitters are arranged such that at least one of the pump laser beams is laterally offset relative to the seed laser beam, and wherein the pump laser beams are configured to effect a gain profile in the gain medium. An output laser beam from the gain medium is a function of at least the gain profile and the seed laser beam.