A device, method and system for causing a controlled collapse of cavities
formed within liquid droplets wherein a pressurized jet comprising a
liquid and nanoparticle material and possibly fuel produces droplets from
the breakup of the jet stream. The liquid droplets are irradiated with
energy to produce and expand cavities formed within the droplets by
irradiation of the nanoparticles contained within the droplets. The
droplets are collided with a target to collapse the cavities within the
droplets. The irradiating and colliding are timed to enhance implosion
energy resulting from the cavities' collapse. The implosion energy and
the fuel in the cavity may be used to activate and sustain a fusion
reaction.