Frequency effects on intense sonoluminescence and bubble dynamics in sulfuric acid

Abstract

Emission intensity increased remarkably with decreasing frequency for both multibubble sonoluminescence (MBSL) and single-bubble sonoluminescence (SBSL) in a concentrated sulfuric acid solution dissolving xenon gas. The spectrum of MBSL in the sulfuric acid showed the emission bands of a large peak at 388 nm and small peaks at 360 and 418 nm. The increase of MBSL intensity at lower frequency was responsible for the increase of the band peak at 388 nm in addition to the increase in continuous spectrum. The bubble dynamics in the sulfuric acid was different from that in water. The intense SBSL was emitted when the bubble was moving on an ellipselike trajectory. The intense MBSL was emitted even when multiple bubbles formed bubble clusters, which could not emit light in the water case.