Stability of small vibrations of a transparent drop in a high-power optical field

The influence of ponderomotive forces on the stability of small vibrations of a transparent drop subjected to a high-power optical field is considered theoretically. The condition for the instability of the vibrations is derived for a low-viscosity liquid. The expression for the threshold incident radiation intensity, above which small vibrations of a drop become unstable, is obtained on the assumption of a Rayleigh distribution of the electromagnetic field inside the drop. Numerical estimates of the instability threshold are obtained for water drops.