Abstract
We developed a new mechanism of laser propulsion whose driving force is a laser-induced bubble that
inhales water. We experimentally demonstrated its propulsion and explained its phenomenon by numerical
simulation and successfully launched a target up by horizontally irradiating a laser and spouting water
up. We clarified that the bubble generated by laser irradiation follows three steps. First, the laser-induced
bubble expands and pushes the surrounding water that spouts from the target’s nozzle. Second, the
collapsing bubble inhales the surrounding water downward, and, the target gets an upward force as a reaction
to the water’s downward flow. We expect this mechanism will be applicable for implementing a
completely new engine that requires no chemical reaction but only the physical reaction of water.
