High-power fiber lasers with integrated rare-earth optical cooler

Abstract

High-power lasers (Raman and traditional solid-state) suffer from heat generated by the quantum defect, which deteriorates their performance. The radiation-balanced technique was proposed to solve the problem in the case of solid-state lasers, and the intrinsic heat-mitigation technique, which relies on coherent anti-Stokes Raman scattering (CARS) was proposed to solve the problem of heat generation in the high power Raman laser. Unfortunately radiated energy increases only linearly with the length of the laser medium in both schemes. We propose a radically new approach to solve the problem of heat generation in lasers. We have considered athermal fiber lasers, where rare-earth (RE) ions based refrigeration sources are incorporated in the body of the devices. This new technique, which has been developed for Raman and traditional solid-state lasers, ensures the exponential growth of radiation along the laser medium and provides almost athermal operation.