Thermal lensing in liquid ethanol induced by high-power diode laser and its effect in beam quality factor M2

In this paper, we measured M-2 factor of a He-Ne probe beam initially with TEM00 mode influenced by thermal lens effect in liquid ethanol. The thermal lensing was induced by focusing a diode laser beam in ethanol. The results of this investigation show that when the diode laser power is increased, the beam quality factor M-2 of He-Ne rises nonlinearly. The results of this study are useful for applications of laser ablation in liquid (LAL) in which beam quality and focused size at the target surface are crucial. According to our results, thermal lens effect induced by high-power laser beam can reduce the beam quality and must be considered in LAL and similar applications.

Automated summary

This study measured the M-2 factor of a He-Ne probe beam influenced by the thermal lens effect in liquid ethanol. The results showed that the beam quality factor M-2 of He-Ne increased nonlinearly with the increase of diode laser power. These findings are significant for applications like laser ablation in liquid (LAL) where beam quality and focused size are important, and highlight the need to consider the thermal lens effect induced by high-power laser beams.