Bjerknes force threshold for stable single bubble sonoluminescence

An investigation of the primary Bjerknes force acting on a bubble in a strong acoustic field is presented. The approach takes into account the nonlinear resonancelike response of small bubbles to strong acoustic pressure amplitudes. It is shown that for high pressure amplitudes even very small bubbles are repelled from the pressure antinode. This result is in contrast to predictions using Bjerknes forces based on harmonic bubble oscillations. The relevance of this high pressure instability for single bubble sonoluminescence experiments is discussed.