Fig. 1. Schematic of experimental setup

Fig. 2. Multimodality measurement of laser-induced single bubble in free liquid under E_L＝468 μJ, R_max＝321.2 μm, and T_osc1 ＝61.2 μs. (a) Photographs of bubble dynamics with an inter-frame interval of 3.33 μs obtained by high-speed camera; (b) time evolution of bubble radius and comparation with R-P simulations; (c) light scattering signal of cavitation bubble collected by photodetector; (d) far-field acoustic signal measured by a piezoelectric transducer

Fig. 3. Bubble maximum radius related to pulse energy and the first oscillation period in free field. (a) Maximum radius as a function of the cube root of pulse energy; (b) maximum radius as a function of the first oscillation period

Fig. 4. Dynamics of bubble pairs with varied relative intervals

Fig. 5. Plasma image of two-point breakdown with variable intervals

Fig. 6. Influence of relative interval on relative magnitude of collapse shock wave and rebound bubble period of coalesced bubble. (a) Relative magnitude of collapse shock wave as a function of relative interval; (b) rebound bubble oscillation period as a function of relative interval

Table 1. Influenced of relative interval on the first oscillation period of coalesced bubble with pulse energy of 450 μJ