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The Schwarz-Hora effect

  1. Jun 12, 2009 #1
    In 1968, H. Schwarz, while trying to modulate an electron beam with optical frequency, discovered that when a 50 keV electron beam was diffracted by a thin crystalline dielectric film illumnated with a laser, electrons produced a diffraction pattern on a non florescent target with the spots of the same color as the color of the laser light illuminating the crystal.

    It was noted the results of the experiment could not be explained by Quantum Mechanics.

    Does anyone know if this experiment has been repeated, or if a successful Quantum Mechanical explanation is availabe?

    H. Schwarz, Bull. Am. Phys. Soc. 13, 897 (1968).
  2. jcsd
  3. Jun 14, 2009 #2
    To the question whether the effect has been reproduced by other authors I refer to the experiments by Andrick and Langhans about the modulation process measured by electron scattering at laser irradiated gas, see reference

    H. Hora, and P.H. Handel, Advances in Elecronics and Electron Physics,
    P.W. Hawkes ed., (Academic Press New York, 1987) Vol 69, p. 55-113

    Abolut the question of the demodulation the relation to entangleing is explained in the google-entry to the Schwarz-Hora effect with the title

    Zeilinger's quantum nonlocality...

    Thanks for the question
    Heinrich Hora, Sydney
  4. Jun 14, 2009 #3
    Thank you very much for replying personally. You just made my day! I will take a look at those articles.
    The effect has caught my attention while studying the "zitterbewegung".

    Are you aware of the work of H De Raedt (University of Groningen), particularly his event by event simulation of Quantum phenomena using deterministic learning machines?

    While reading one of Ed Jaynes' papers on zitterbewegung it occured to me that it might be possible to explain the Schwarz-Hora effect in a deterministic local manner.
    Last edited: Jun 14, 2009
  5. Jun 15, 2009 #4
    Thanks for your comment.
    I did not come acros thework of H. de Raedt.
    The work of Ed Jaynes is very interesting and eye-opening, and Dirac's Zitterbewegung has been discussed when I had the visit of Paul Dirac in 1975 in Sydney. From my discussion with Nathan Rosen I conclude that the relation of nonlodaclity may well be an access for clarification of the demodulation process.
  6. Jun 16, 2009 #5
    The effect looks really interesting. Although a quick search didn't show many confirming experiments. What other measurements have been done on the electrons and their emitted light? Spectroscopy? Autocorrelation? Does the type of screen matter?
  7. Jun 16, 2009 #6
    There are very very many more questions to be checked experimentally and theoretically. Are you interested and have funds & capacity to do this? I shall be pleased to support this. You may contact me
    All the best
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