Hello, my name is Chris Petersen. I am a Physics major at the University of California Santa Barbara and no longer at Shasta College in Redding, CA. While at Shasta College I completed an independent study on single bubble Sonoluminescence (SBSL). Under Tom Masulis and Joe Polen, Douglas Manning and I were successful in making Sonoluminescence.
This is an incredible phenomenon where sound can be converted into light!
History:
Sonoluminescence was discovered by accident (like most applications in science) in the early 1930's by a pair of German Physicists @ the University of Cologne. It hasn't been until the last ten years that theorists and researchers have really given sonoluminescence an audience. The leading work has being done by Seth J. Putterman, Robert A. Hiller and Bradley P. Barber at UCLA. While this group has published many papers on sonoluminescence the most popular of their papers can be found in Scientific American Feb. 1995 Vol.272.
Overview:
The phenomenon of single bubble sonoluminescence can be produced as a table top physics project. From 100 to 200 dollars one can make sonoluminescence. To make SBSL (Single Bubble Sonoluminescence) one has to have a bubble (of plain air) surrounded by water in a spherical flask and then bombarded by high frequency sound waves.
This causes the bubble to contract and as this happens something very spectacular happens! The bubble starts emitting light. Light, as in photons are being emitted from this bubble of air (now plasma) that is under contraction. I hope that you are as amazed as I was the first time I learned of this effect (that is if you are not already looking for info on SL).
Specifics:
As if the emitting of light isn't strange enough one also has tremendous pressures and temperatures that turn the air in the bubble into plasma. Temperatures have been estimated to range from 10 to 100eV (1eV = 11,600K or 20,420 degrees F). O.k. the number you want is 2,042,033 degrees F @ 100eV; that is as hot as the corona of our sun. The pressures are as high as 200Mbar (1Mbar = 10^11 Pa) in the core of the imploding bubble. This pressure is equal to 1.974*10^8 or 19,743,336 atm (atmospheres). One atmosphere is the amount of pressure that we live in at sea level. The use of different gases has also shown a very peculiar happening. If the surrounding water is doped with 1% Argon gas the emission of light grows by a factor of >100. Other noble gases also have shown an effect on the amount of photons emitted.
Theories and Oddities of Sonoluminescence:
Into the unknown now. The Physics community is presently working on hypotheses for the mechanisims of Sonoluminescence.
1) One of the most dynamic of hypotheses on SL is one provided by Claudia Eberlein. She proposes that the 12ps flashes of SL is generated by photons being emitted by Hawking Radiation. This is the same radiation that is generated by a black hole. Comparitive to other hypotheses the Hawking Radiation model correlates predicted and actual temperatures quite nicely.
2) Another is the Properetti's Theory. This theory states that Sonoluminescence takes place due to tiny jets of liquid shooting across the bubble's interior. These proposed jets are traveling at supersonic speeds (Mach 4, Putterman) and when a jet would slam into the side of the bubble opposite of the projection side it would fracture.
When the jet "fractures" it would release energy in the form of light. This theory could also help with theunderstanding of why the use of noble gases in the surrounding liquid can increase the photon output. Prosperetti believes that the addition of the innate noble gases creates flaws or weaknesses in the water's crystal-like structure providing the fractures a foothold in which to begin. This would increase the amount of fractures that would take place in the Sonoluminescencing bubble. Hence the emission would be increased.
I hope that I have wet your appetite, as I learn more I will be updating the site. I hope you keep checking in!
On 2/26/97 we got a little GLOWING BUBBLE one word can easily sum up achieving
Sonoluminescence: WAHOO!!
Quotes:
After a certain high level of technical skill is achieved, science and art tend to coalesce in esthetics, plasticity, and form. The greatest scientists are always artists as well.
-Einstein
An hour sitting with a pretty girl on a park bench passes like a minute, but a minute sitting on a hot stove seems like an hour.
-Einstein, Einstein's explanation of Relativity for several persistant reporters
The voice of the intellect is soft one, but it does not rest until it has gained a hearing. Ultimately, after endless rebuffs, it succeeds. This is one of the few points in which one may be optimistic about the future of mankind.
- Sigmund Freud, The Future of an Illusion
The most beautiful experiance we can have is the mysterious . . . it is the fundamental emotion which stands at the cradle of true art and true science.
-Albert Einstein
Further Quotes
Further Info:
The Acoustic Bubble by T.G. Leighton, Institute of Sound and Vibration Research, The University, South Hampton,
U.K. Available from Academic Press @ Academic Press : APNet Home Page
If you would like to make Sonoluminescence follow this link to check out my HOW TO: CPeter2001's Home Page 2
