Mechanism of sonoluminescence

Sonoluminescence is a phenomenon that occurs when a small gas bubble is acoustically suspended and periodically driven in a liquid solution at ultrasonic frequencies, resulting in bubble collapse, cavitation, and light emission. The thermal energy that is released from the bubble collapse is so great that it can cause weak light emission.[1] The mechanism of the light emission remains uncertain, but some of the current theories, which are categorized under either thermal or electrical processes, are Bremsstrahlung radiation, argon rectification hypothesis,[2] and hot spot. Some researchers are beginning to favor thermal process explanations as temperature differences have consistently been observed with different methods of spectral analysis.[3] In order to understand the light emission mechanism, it is important to know what is happening in the bubble's interior and at the bubble's surface.

A setup similar to the following is required to create a bubble that can sonoluminesce.
  1. ^ Michael P. Brenner (2002). "Single-bubble sonoluminescence". Reviews of Modern Physics. 74 (2): 425–484. Bibcode:2002RvMP...74..425B. CiteSeerX 10.1.1.6.9407. doi:10.1103/RevModPhys.74.425.
  2. ^ Thomas J. Matula; Lawrence A. Crum (1998). "Evidence for Gas Exchange in Single-Bubble Sonoluminescence". Physical Review Letters. 80 (4): 865–868. Bibcode:1998PhRvL..80..865M. doi:10.1103/PhysRevLett.80.865. S2CID 115140924.
  3. ^ K.S. Suslick; W.B. McNamara III; Y. Didenko (1999). "Hot Spot Conditions During Multi-Bubble Cavitation" (PDF). Sonochemistry and Sonoluminescence: 191–205. doi:10.1007/978-94-015-9215-4_16. ISBN 978-90-481-5162-2.