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For elastography measurements, Muthupillai et al. assumed that a displacement of a few hundreds of nanometers should be sufficient to perform shear wave elastography \cite{7569924}. However, displacements of 5 to 20 $\mu$m are usually required, which is slightly higher than the maximum displacement observed here (about 2 $\mu$m in the chicken breast sample). The minimum energy of the laser (532 nm, 10 ns, 50 80  mJ, 5 mm diameter) used in our experiments to get a shear wave is about ten twenty  times higher than the maximum exposure permissible as given by the current American National Standard Institute (Z136.1-2000) for skin \cite{ANSIZ1361}, but a value which is also used in typical photoacoustic imaging experiments \cite{Ku_2005}. This value  is also about fifty times lower than the typical energy used for skin tatoo removal \cite{8352621}. There are different ways to obtain measurable displacements with a lower laser energy: using more efficient speckle-tracking algorithm, decrease the ultrasound acquisition frame-rate, or averaging over multiple experiments.Shear wave frequency in elastography ranges typically between 50 and 500 Hz, with higher frequency meaning better spatial resolution. The experiments demonstrated that these frequencies can be reached, although the mechanism explaining this particular frequency is not clear yet.  The laser also has the advantage of being non-contact and totally remote. For example, Li et al. have proposed to induce surface acoustic waves by laser to measure elastic properties of biological thin layers like skin or cornea \cite{li2011elastic}, \cite{li2014laser}. Moreover, a laser probe can be made extremely small (smaller than 100 $\mu$m diameter if required), especially if optical fibres are employed, for example for insertion in small vessels. Additionally, the shear wave source emits very weak electromagnetic noise (apart from the laser device itself), so it can be quite convenient for magnetic resonance elastography measurements, which are currently using external drivers or non-magnetic ultrasound probes. Moreover, the laser probe could help to shape precisely the shear wave shape, with focusing capabilities for example (see for example \cite{noroy1993laser}).  In summary, this study presented observation of elastic shear waves generated in soft tissues using a laser beam. The involved phenomenon was investigated. Experiments in chicken breast sample showed the feasibility of the elastography method using a laser beam as a shear wave source.  The authors would like to thank Damien Garcia for lending the laser device. Pol Grasland-Mongrain received a FRM SPE20140129460 CRSNG  post-doctoral grant. The authors declare no conflict of interest in the work presented here.