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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}, displacements of the order of the micrometer are usually required in ultrasound or 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 (10 mJ)  of our the  laser (532 nm, 10 ns, 10 mJ, 5 mm diameter) beam  used in our experimentsto 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} and a few hundred times lower than  the laser energy one  used 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, like high frequency (100 MHz) ultrasound imaging or Optical Coherence Tomography technique.  In a practical application in the human body, different strategies could be adopted to comply to ANSI standard: observe the medium with high resolution imaging technique, able to track displacements of a few nanometers, like high frequency (~100 MHz) ultrasound imaging, or Optical Coherence Tomography technique as done by Li et al. \cite{Li_2011}; or emit the laser beam on a protective absorbing layer, for example a black sheet sticked to the patient organ.  To sum up this article, we have presented experimental observations in soft medium of elastic shear waves generated by a laser beam. The involved phenomenons were investigated and we distinguished thermoelastic and ablative regimes. Theoretical displacements are close were in good agreement  to experimental measurements. Numerical studies show showed  comparable displacement propagation patterns as in experiments. experimental ones.  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.