Lasers have revolutionised the world, impacting fields from medical science to military technology, and from academia to industry. Working on the principle of stimulated emission, lasers have evolved into many kinds, including solid-state lasers. These solid-state lasers play a crucial role in driving the technological advancements of the modern era. One of the limitations of solid-state lasers is their power-hungry nature. A solarpumped laser opens a new horizon in meeting energy demands by harnessing unlimited energy from the sun. However, it faces the heating problem. Radiationbalanced lasers represent an approach in solid-state laser technology by addressing one of its limitations—heat accumulation in the gain medium. By carefully engineering the pump and emission wavelengths and using anti-Stokes fluorescence, Radiation Balanced Laser (RBL) can achieve a thermally neutral operation, where optical refrigeration counters the heat generated during lasing. This work presents a feasibility study of Solar-pumped RBL, which investigates the spectral criteria, intensity thresholds, and material parameters required to reach a net-zero or negative heat load during laser operation using solar pumping. The results demonstrate that under optimised conditions, including precise control of pump wavelengths and cavity losses, Solar-pumped radiation-balanced lasing is achievable, offering significant advantages in thermal management. This work also presents the limitations which arise from parasitic absorption.
Mohammad Sahil (2026) studied this question.