A laser. The novel laser includes a gain medium, a pump source adapted to optically excite the gain medium in a first location, and a resonator adapted to extract energy from the gain medium in a second location distinct from the first location. In an illustrative embodiment, the gain medium is comprised of a plurality of solid-state gain particles suspended in a fluid. The gain medium is adapted to flow, and optical excitation of the gain medium occurs outside of the resonator. In a preferred embodiment, the flow velocity and the density of gain particles in the gain medium are adjusted for optimal absorption efficiency during optical excitation and then for optimal extraction efficiency in the resonator. In addition, the resonator may be shaped for optimal extraction efficiency, while pump modules that hold the gain medium during optical excitation are shaped for optimal absorption efficiency.