Conical bubble photoluminescence from rhodamine 6G in 1, 2-propanediol

A modified U-tube conical bubble sonoluminescence device is used tostudy the conical bubble photoluminescence. The spectra of conicalbubble sonoluminescence at different concentrations of rhodamine 6G(Rh6G) solution in 1,2-propanediol have been measured. Results showthat the sonoluminescence from the conical bubbles can directlyexcite Rh6G, which in turn can fluoresce. The light emission of thiskind is referred to as conical bubble photoluminescence. The maximumof fluorescence spectral line intensity in the conical bubblephotoluminescence has a red shift in relative to that of thestandard photo-excited fluorescence, which is due to the higherself-absorption of Rh6G, and the spectral line of conical bubblephotoluminescence is broadened in width compared with that ofphoto-excited fluorescence.