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When a laser beam of sufficient energy is incident on a medium, the absorption of the electromagnetic radiation leads to an increase of the local temperature. Due to thermal effects, displacements occur in the medium. These displacements can then propagate as elastic waves. Elastic waves are separated in two components in a bulk: compression waves, corresponding to a curl-free propagation; and shear waves, corresponding to a divergence-free propagation \cite{aki2002quantitative}. Measures of the compression and shear waves is notably used as a method of inspection to reveal potential cracks in a solid such as a metal. In a medical context, induction of compression waves by laser has been studied with the development of photoacoustic imaging \cite{Xu_2006}, \cite{22442475}. Elastic waves used in photoacoustic imaging are typically of a few megahertz: at this frequency, in a soft tissue, shear waves are quickly attenuated, typically over a few microns, and only compression waves can propagate over a few centimeters.    In the other hand, shear waves have drawn an increasing interest in medical imaging, with the development of shear wave elastography techniques for the last two decades \cite{muthupillai1995magnetic}, \cite{sandrin2002shear}. As its names indicates, this term covers the techniques used to measure or map the elastic properties of biological tissues using shear wave propagation. The shear modulus, directly proportional to Young's modulus in soft tissues, varies of several orders of magnitude between different tissues in human body and potentially offers a good contrast. As a shear wave propagates in an organ at a speed proportional to the square root of the shear modulus, measuring its speed throughout the organ allows to compute the shear modulus of the tissue. Shear waves can be induced by an external vibrator \cite{muthupillai1995magnetic}, a focused acoustic beam \cite{sarvazyan1998shear}, \cite{11937286}, the Lorentz force \cite{16051039}, \cite{grasland2014elastoEMarticle}, or natural body displacements \cite{gallot2011passive}, \cite{Zorgani_2015}, \cite{Weaver_2012}. Shear wave elastography techniques have been successfully applied for the detection of various pathologies in organs such as the liver \cite{sandrin2003transient}, the breast \cite{goddi2012breast}, \cite{sinkus2005viscoelastic}, the prostate \cite{cochlin2002elastography}, \cite{12878247}, the arteries \cite{schmitt2010ultrasound} schmi\cite{Schmitt_2010}  and the eye cornea \cite{tanter2009high}, to name a few examples. Very recently, Li et al. have used induce surface acoustic wave induced with a laser to assess bladder wall elasticity \cite{25574440} and cornea elasticity \cite{22627517}. In this study, we show that study the induction of  shear wavescan be induced in soft tissues  by a laser beam. beam in soft tissues.  We have been able to distinguish two different regimes depending on laser energy. We propose a physical model to describe the observed phenomenons. We finally applied the technique in a biological tissue to show the potential application in shear wave elastography. In the first experiment, illustrated by Figure \ref{Figure1}, we used a Q-switch Nd:YAG laser (EverGreen 200, Quantel, Les Ulis, France), which produced a pulse of energy $E$ = 200 mJ at a central wavelength of 532 nm during 10 ns in a 5 mm diameter circular beam. Z is defined here as the laser beam axis and origin of coordinates (0,0,0) as the laser impact location on the medium. The laser beam was absorbed in a 4x8x8 cm$^3$ tissue-mimicking black mat phantom made of water and of 5\% polyvinyl alcohol and 1 \% black graphite powder. A freezing/thawing cycle was applied to stiffen the material to a value of 15$\pm$5 kPa \cite{17375819}. To observe the resulting shear waves, the medium was scanned with a 5 MHz ultrasonic probe made of 128 elements connected to a Verasonics scanner (Verasonics V-1, Redmond, WA, USA). The probe was used in ultrafast mode \cite{bercoff2004supersonic}, acquiring 4000 ultrasound images per second during 30 ms. Due to the presence of graphite particles, the medium presented a speckle pattern on the ultrasound image. Tracking the speckle spots with an optical flow technique (Lucas-Kanade method with a 64x5 pixels window) allowed to compute Z-axis component of the displacement in the medium. Displacements along time were then filtered from 200 to 800 Hz using a 5th order Butterworth filter.