Influence of the active element diameter on the output power of a cw solid-state laser

An experimental investigation was made of the distribution of the intensity of the pump radiation and heat evolved in an active element as a function of its diameter. When the dependence of the pump enclosure efficiency on the element radius was linear, the optimal diameter of the active element was directly proportional to the pump power and inversely proportional to the losses in the active element. The results of determination of the optimal radius of the active element were in agreement with calculations.