Fig. 1. (a) Slab of active media, (b) heat deposition distribution and thermal effects numerical model results in the form of resulting temperature and OPD distributions.

Fig. 2. (a) Example of actuators position in a square DM. SA defines the size of the side actuators; AR is the size of the active region (part of the DM illuminated by the laser beam). (b) Reports the Strehl Ratio obtained with the correction of the DM realized in different configurations as reported in the legend in function of the DM stroke.

Fig. 3. Stroke in function of glass diameter (with fixed aspect ratio of 25) and PZT thickness with voltage held constant to 150 V.

Fig. 4. Pictures of the characterized DMs. (a) Dipole $6\times 6$, (b) HiLASE $7\times 7$, (c) HiLASE $6\times 6$ with the control box.

Fig. 5. Results of characterization of three DMs in terms of Legendre modes generation capability. The results are compared with the estimated Legendre decomposition of the wavefront of 10 J multi-slab amplifier, which was calculated by the Miró model.

Fig. 6. (a) Cross-section of the spot obtained with by the application of the wavefront calculated with the thermo-optical simulations and after the correction with the closed loop. (b) Spot image of the aberrated wavefront. (c) Spot after the correction with the closed loop operation.

Table 1. Parameters of the characterized DMs.