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Sonoluminescence works as an LED possibly?

  1. Dec 3, 2014 #1
    I am a senior in high school researching sonoluminesce. Me and my teacher were hypothesizing the mechanism that could cause it and discussed the possibility of the bubble and water system having LED-type qualities, as an LED is light emitted by electrons falling into holes when excited by thermal or other energetic excitations. Furthermore, the bubble releases light after the compression, possibly hinting that thermal energy has to be added for the light to be emitted like an LED, and the amount of thermal energy would be so high due to the difficulty energy-wise on creating a noble gas LED, since noble gases are inside the bubble. I wanted to ask you if this is a plausible idea and what kind of mathematics, physical laws and equations would I have to acquaint myself with in order to further my hypothesis. Also what variables should I be measuring for this idea. I thought of PV=nRT but at the largest size of the bubble, P would just about equal zero since it is just about a vacuum, and then so would n equal zero for the same reason. I just wanted to know what should I expect and learn now for when I am experimenting later. Thank you for your help and time!

    I wanna have a huge discussion on what everyone thinks sonoluminescence can be caused by!
  2. jcsd
  3. Dec 4, 2014 #2


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    Disclaimer: I know next to nothing about sonoluminescence, so I will only make general comments about the approach.

    The first thing to do is to get familiar with existing theories of sonoluminescence. At a minimum, start with Wikipedia.

    "Hole" as a very specific meaning, and I don't know how you could have holes without a solid state. Do you know what is the general mechanism by which atoms or molecules emit light? Before saying that it works like a LED, you would have to show that light emission does not follow from the known mechanisms for atoms or molecules.

    How can P be close to zero? The bubble is inside a liquid, and sonoluminesce is produced when the bubble cavitates, meaning that the pressures inside are huge.

    Also, in that equation, n is the number of moles, so if you say it is zero, it means you have no gas. Since one mole is ##6 \times 10^{23}## particles, n can be extremely small and you will still have many particles.
  4. Dec 4, 2014 #3
    Well when the bubble is at its maximum radius it is basically a vacuum. Therefore the pressure within the bubble should be negligible.
  5. Dec 4, 2014 #4


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    Before you try to make any kind of speculation to explain something, you must first understand all that we know about that something. Do you know enough of what we know about sonoluminescence and LEDs? For example, look at the light spectrum that comes out of each of those two phenomena. Do do you think they look the same, so much so that you think they are of the same "quality"?

    Please read a bit more about sonoluminescence. This link has an example of the light spectrum from such a source. Now do some homework and compare that with your typical LED source. Why would you think they have the same "quality"?

  6. Dec 4, 2014 #5
    I put together that both LED's and sonoluminescent bubbles both need thermal excitations for light production. I figured they are both also very efficient in their energy conversions as well.
  7. Dec 4, 2014 #6
    Last page, 1st column a paragraph or two before the section "Nobel Addition"
  8. Dec 4, 2014 #7


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    This is a vague description, and it is also wrong for LEDs. Why do you think LEDs need a p-type and n-type semiconductors to work?

    You are not up to speed of the results of each of these two phenomena. So please read up on the results FIRST. Again, just look at the light spectrum given off by each of them. You will be hard-pressed to convince anyone that these have the same "quality". So why would you think they have the same mechanism?

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