Study of active media based on microparticles of solid-state laser materials

Active media based on particles of solid-state laser materials distributed in liquid or gas may provide a new solution to the problem of heat removal from laser media. We propose active media based on particles of LiF crystal with F₂ color centers, as well as of Nd³⁺-doped crystals and glasses. Mixtures of index-matched liquids with glass and crystal particles, methods of their preparation, and their optical characteristics are considered. The laser characteristics of the active media under excitation by nanosecond laser pulses are compared. A “slurry laser” based on a dense mixture of LiF:F₂ microparticles with an index-matched liquid is demonstrated. Lasing was obtained in small neodymium pentaphosphate crystals (NdP₅O₁₄) and unpolished bulk pieces of concentrated neodymium phosphate glass in immersion liquids.