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I CMA (Cylindrical Mirror Analyzer)

  1. Jul 5, 2016 #1


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    I'm supposed to be working with a CMA (Cylindrical Mirror Analyzer), but I'm more interested in the physics behind it. This is the instrument in question that we are looking to get:


    We want it to look at different eV levels of different wavelengths and how it compares to the theoretical values we are looking to get. I know it works off of photoemission, but kind of confused how the readings work? I'm confused on how/why it works and there's nothing on Wikipedia that I can find on it to go off of. This is similar to the set up we are looking at:


    Where the Ion source will be something like an electron gun, and the electron gun in the photo would be the microCMA.

    What makes this set up different from say a spectrometer, or using a CCD camera or something else of the sort? What's the advantage here that I'm not seeing?
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  3. Jul 6, 2016 #2
    Aren't you detecting electrons not photons? Certainly for Auger electron spectroscopy it's the electrons you detect, not the photon.
  4. Jul 6, 2016 #3


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    It is analogous to a spectrometer, or to be specific, electron spectrometer since it analyzes only electrons. However, it has the capability of having a higher energy resolution, and is able to change the range of energy of interest within its analyzer window.

    All the analyzer does is look at the energy spectrum (although for spherical analyzer, both energy and momentum spectrum can be obtained) of the electrons. Where the electrons come from doesn't really matter, and that is where the material or source being studied comes into play.

    I'm not sure if you are simply asking for a conceptual understanding of what it does, or if you are really looking for the nuts-and-bolts of how it works in detail (the latter you can easily do a search on).

  5. Jul 6, 2016 #4


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    Yes, my understanding was that it was like a spectrometer but wasn't sure what the advantage was.

    I thought we were going to be looking at the diffraction grating, but you are correct. It's the Auger electrons we'll be looking at. I was looking more for a deeper understanding than conceptual on how a CMA works, can't find much from Google (well a couple things, but doesn't leave me satisfied). Although the Wiki page gave me a fairly clear understanding of the set up and cleared up some of the confusion, I'm still not sure what goes on in a CMA.

    Is there a technical manual of one or a book to reference? Or would I be left to look at several concepts and piece the information together? Thanks btw.
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