Influence of aberrations on fundamental mode of high power solid-state lasers

Summary form only given. The availability high power laser diodes permits to pump with high efficiency a large volume of gain medium, and it allows in principle to extract more power from laser cavities having a large mode size. However, the larger the mode, the more important the influence of the thermal aberrations. This motivated recent researches on homogeneous pumping chambers to reduce these aberrations. We present experimental measurements of the thermal aberrations of a high power diode-pumped Nd:YAG rod laser head, and show that residual aberrations are mostly astigmatism and spherical aberration. In order to determine the influence of these aberrations, we completely modeled a standard cavity, including thermal aberrations and gain saturation.