Figure 4.
The image sequence shows an 8.5 μm DDFP liquid microdroplet undergoing the ADV process initiated by a single pulse of 16 cycles at 7.5 MHz and 3.6 MPa PNP. The “*” demarcates the presence of the ultrasound pulse in the field of view, and the arrow indicates the direction of the ultrasound wave. Visually, perforation of the bubble resulting in a bubble torus is seen approximately 1 μs after the initial nucleation. A combination of elevated pulse length and acoustic pressure results in what appears to be a violent ADV process.