Direct observation of period-doubled nonspherical states in single-bubble sonoluminescence

Abstract

We present direct observations of period doubling in the flash to flash pulse heights in single-bubble sonoluminescence. States involved are stable, spherically symmetry broken. Observations are made using seven detectors distributed in the equatorial plane of the bubble. Contrary to earlier experiments by Holt et al. [Phys. Rev. Lett. 72, 1376 (1994)], where period doubling was observed in the time intervals between flashes but not in the pulse heights, we observe period doubling in pulse heights, but no corresponding period doubling is seen in the time intervals. In parameter space the period doubling is observed below the n=2 shape instability boundary line where extinction is shown to take place.

Acoustic energy radiated by nonlinear spherical oscillations of strongly driven bubbles

“…As seen in experiments (Gaitan & Holt 1999;Levinsen et al 2003) and numerical calculations, higher order oscillations of the bubble surface also play a role in a part of the parameter space (Holzfuss 2008). The instabilities that occur limit the available state space.…”

Second Mode of Recycling together with Period Doubling Links Single-Bubble and Multibubble Sonoluminescence

“…The size of the equilibrium radius at 25% is found to be 6 m and the sound pressure at the threshold to be 1.5 atm at the instability level in a previous experiment. As we have shown for air-seeded stable and type 1 SBSL [2,7,8], period doubled light emission is observed for the type 2 mode. Since the emission in all cases is spatially anisotropic, this phenomenon is presumably coupled to shape distortion.…”

“…The gas in the surviving part of the bubble thus mainly consists of argon. In what follows we shall present arguments that the new recycling mode is related to mostly air filled bubbles that reach the instability threshold before the burn off becomes efficient.The vessel and the filling procedure is described in detail in a previous publication [8] with experiments performed at drive frequency 22.114 kHz and temperature 9 C. However, the detection and data collection systems have undergone several changes. The detection system consists of eight photomultiplier tubes (PMT Hamamatsu R3478 & R2076, rise time 1.3 ns) to provide spatial information.…”

“…The vessel and the filling procedure is described in detail in a previous publication [8] with experiments performed at drive frequency 22.114 kHz and temperature 9 C. However, the detection and data collection systems have undergone several changes. The detection system consists of eight photomultiplier tubes (PMT Hamamatsu R3478 & R2076, rise time 1.3 ns) to provide spatial information.…”

Including ionisation in a simple model of single-bubble sonoluminescence

“…This stability region is not well defined; different physical conditions are suspected to extend the parameter range of stability [16]. Stable, non-spherical oscillations have produced SL outside this region [7,19,25]. The parameters used for this study are mostly within this region.…”