Modeling of optical inhomogeneities in Cr$^{2+}$:CdSe lasers with a moving active element

The work is devoted to modeling the heating of moving active elements from CdSe and estimates emerging optical inhomogeneities. Active elements in the form of a parallelepiped are considered, which rotated in a circle perpendicular to the generation axis. As a result of calculations, it was found that the temperature distribution in the active element that occurs during the operation of the laser can be represented as the sum of two components. The first component is formed due to the balance between heat emission in the active element due to pumping and heat removal from it, which leads to the appearance of an aberration, which is the sum of “tilt” and “defocusing”. The second component is formed directly during the passage of the pump spot through the active element, is determined only by the heat release density and is not related to the cooling method of the active element. It leads to the appearance of “Gaussian” aberration, the amplitude of this aberration is directly proportional to the power of heat emission and inversely proportional to the frequency of rotation of the active element.