Kenneth Suslick University of Illinois at Urbana-Champaign CHE-0079124

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Kenneth Suslick University of Illinois at
Urbana-Champaign CHE-0079124
Like fireflies, bubbles trapped and energized by
ultrasound emit light in a periodic rhythm. By
holding a single bubble of gas in a standing
acoustic wave and driving it into pulsations,
sound energy is converted into light with
clocklike regularity. At the same time, the
intense energy is used to blow molecules
apart. Professor Ken Suslick and postdoctoral
associate Yuri Didenko at the University of
Illinois are the first to quantify these effects
in a single bubble. Less than one millionth of
the sound energy is converted into light. A
thousand times more energy goes into the
formation of atoms, molecular fragments and ions.
The largest part of the sonic energy is converted
into mechanical energy, causing shock waves and
motion in the liquid surrounding the gas bubble.
Movie a stroboscopic image of two cycles of a
cavitating single bubble in a spherical acoustic
field at 25 kHz. Each cycle is 50 microseconds
long. The sonoluminescence and sonochemistry are
generated at the minimum of the bubble collapse.
Double-click on icon above to play the Single
Bubble Cavitation movie