Study on phase change of Gaussian beam induced by thermal blooming effect

When a high-power laser beam propagates in an absorbing medium, the thermal blooming effect cause the phase distortion of the beam, which will seriously affect the beam quality. In this paper, with the help of the laser propagation theory and thermo-optic coefficient experiment, the phase change of Gaussian beam propagating in various concentrations of ink-ethanol is investigated. The result shows that the phase change is proportional to the input power, which may provide the theoretical and experimental basis for phase compensation, and have potential applications in the adaptive optics, underwater optical communications, biological tissue imaging and other related field.