Abstract: The present invention relates to a process for the growth of a crystalline solid by inching then cooling a crystallization material (2), in which the crystallization material (2) spread over a support is melted in the operating region (4) of a heat source. According to this process: outside of the operating region, the crystallization material (2) is spread over at least two areas of different compositions (31, 32, 33, 34, 33), and the crystallization material (2) being spread over a length greater than the length of the operating region (4), a movement of the operating region (4) relative to the crystallization material (2) is carried out so as to place successively in the operating region (4) then outside of the operating region, portions of the crystallization material of different compositions. This process is used to manufacture laser crystals having a controlled spatial distribution of doping.