Bubble oscillations driven by self-similar sound

Single-bubble sonoluminescence occurs at the rapid collapse of the bubble after a long and slow expansion, and the bubble oscillation in the higher harmonic modes leads to the rapid collapse. Based on the idea of linear superposition, the concept of self-similar driving, driving the bubble by the sound pressure similar to its oscillation, has been put forward. The numerical simulation indicates that the rapid collapse of the bubble can be enhanced under the drive of the self-similar sound. Compared to sinusoidal driving, the self-similar sound consisting of the fundamental and its second harmonic, results in a remarkable increase of light emission. The investigation gives an intuitionistic picture for the optimized multi-frequency driving and proposes an experimental method to upscale the sonoluminescence.