If you can explain how the sound turns into light inside the bubble, a Nobel Prize waiting; do it Zimme ,keep the cash in Sweden.
https://en.wikipedia.org/wiki/Sonoluminescence
The wikipedia article seems to explain the process pretty well. The sound causes pressure fluctuations in the water, and the bubbles are created by temporary zones of very low pressure. When the bubble then collapses, the incompressibility of water results in an extremely high, short-lived, pressure spike, allowing the small amount of gas (water vapor or gases normally dissolved in the water) to be heated via compression to the point that they incandesce. The amount of gas in the temporary bubble is very small, resulting in a very small amount of very high temperature plasma in the center. If the amount of gas was larger, the bubble would not collapse as far before the pressure built up, resulting in less energy being spread across a larger amount of gas, and lower final temperatures. The amount of energy available to produce the effect is based on the size of the bubble produced (the larger, the more energy available and the higher the peak temperature) and the amount of gas which evaporates into it (the more gas, the LESS energy available and more gas to put it into, resulting in lower peak temperatures).
Mike