Finally, the dependence of the shear wave amplitude versus laser energy was quantitatively investigated by increasing the laser beam energy from 10 to 200 mJ. Amplitudes were averaged over four experiments for each energy level and successive energy levels were randomly chosen to avoid any time-related bias. In addition, impact location was changed after each laser emission to avoid any potential local degradation of the medium. Shear wave amplitude was measured as the mean square amplitude at t = 1 ms of the displacement estimated from ultrasound images between 0 and 10 mm of the medium surface, which was an arbitrary location where shear waves demonstrated high amplitudes. Resulting measurements are illustrated in Figure \ref{figDepEnergy}. Two linear dependencies are observed: one from 10 to 40 mJ, with a slope of 1.05 (R$^2$ = 0.87), and one from 30 to 200 mJ, with a slope of 2.18 (R$^2$ = 0.97). This is in accordance with the theory that displacement is linearly dependent on energy at low energies, i.e. in the thermoelastic regime, but quadratically dependent at high energies, i.e. in the ablative regime. The threshold around 30-40 mJ is specific to our material characteristics, notably its absorption coefficient.