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Quantum dots unstable?

  1. Sep 16, 2003 #1
    Sandia National lab reported that quantum dots absorb near UV and re-emit at the visible range. It's wavelength shifts to a longer wavelength with 60% efficiency.

    Does this mean quantum dots are unstable? Since they add mass to themselves. This makes them something different from what they were initially. I come to this conclusion that they add mass by the knowledge that the quantum dots absorb a high frequency photon and release a slower moving one.

    Thoughts?
    Paden Roder
     
  2. jcsd
  3. Sep 16, 2003 #2

    chroot

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    I have the feeling the dots emit more low-frequency photons than they absorb high-frequency photons.

    Also, all photons move at the same speed: c.

    - Warren
     
  4. Sep 16, 2003 #3
    What is a quantum dot?
     
  5. Sep 16, 2003 #4

    chroot

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    An effectively zero-dimensional confinement apparatus for electrons.

    - Warren
     
  6. Sep 17, 2003 #5
    You know what I meant (or so I hope) when I said slower moving one. Lower frequency.
    Paden Roder
     
  7. Nov 6, 2004 #6
    The excess energy is converted to thermal (lattice vibrations), and ultimately coupled out through the surface to the surrounding medium.
     
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