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In a context of shear wave elastography, the thermoelastic regime is a priori preferred to the ablative regime, as it is less destructive. If  Muthupillai et al. assumed that a displacement of a few hundreds of nanometers should be sufficient to perform shear wave elastography \cite{7569924}. However, \cite{7569924},  displacements of the order of the micrometer is are  usually required in ultrasound or MRI, which MRI elastography: this  is higher than the displacement observed at 10 mJ (thermoelastic regime) and about the same order of magnitude at 200 mJ (ablative regime). The minimum energy of our laser (532 nm, 10 ns, 10 mJ, 5 mm diameter) used in our experiments to get a shear wave is incidentally 2.5 times above the maximum exposure permissible for skin given by the Z136.1-2007 standard of the American National Standard Institute \cite{ANSIZ1361} - a value which is also used in typical photoacoustic imaging experiments \cite{Ku_2005} but also and  a few hundred times lowerthan  the typical laser  energy used for in  skin tattoo removal procedures  \cite{8352621}. In a practical application on human body, different strategies could be adopted to overcome this problem: emit the laser beam on a protective absorbing layer, for example a black sheet sticked to the patient organ; Or observe the medium with high resolution imaging technique, able to track displacements of a few nanometers, likevery  high frequencyultrasound  (100 MHz) ultrasound imaging  or Optical Coherence Tomography technique. To sum up this article, we have presented experimental observation observations in soft medium  of elastic shear waves generated in soft tissues using by  a laser beam. The involved phenomenons were investigated and we distinguished thermoelastic and ablative regimes. Theoretical displacements are close to experimental ones. measurements.  Numerical studies show comparable displacement propagation patterns as in experiments. The authors would like to thank Damien Garcia for lending the laser device and Simon Bernard for his help in Matlab coding. Pol Grasland-Mongrain received a CRSNG post-doctoral grant. The authors declare no conflict of interest in the work presented here.