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A Reversing the Faraday effect to get an induced current

  1. Jan 14, 2019 #1
    Hi all!
    I was thinking if it is possible to revert the Faraday effect.
    If I have a magnetic field, it interacts with EM wave (light) by changing its polarisation.

    Can I got a variable magnetic field interacting with polarised light so that I can get induced current in a coil?

    I can understand it is something similar to Nantenna, and I can understand that I need nano coils which are difficult to realize but I was thinking more to utilize special materials as mean (or crystals) to be at the right wave lenght to get induced current in a coil.

    Is there any research in this? any link to suggest to me?
  2. jcsd
  3. Jan 14, 2019 #2


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    Science Advisor

    It is not just "something similar to" an antenna, it is an antenna. This is what an antenna does - it generates a current by interacting with an EM wave. There is certainly research on making antennas small enough to interact with light, such as this article.
  4. Jan 14, 2019 #3


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    Gold Member

    Faraday Effect is when we apply a very strong magnetic field to a transparent material and observe a slight rotation of polarisation. The reverse process does not seem likely due to the relative energies involved. On the other hand, as has been mentioned, we can use receiving antennas which are similar in size to the wavelength, including coils, to extract energy from an EM wave. I think a difficulty with optical frequencies is making low loss transmission lines for the received power.
  5. Jan 15, 2019 #4
    Thanks both for the kind answers and article.

    Well, I was thinking to have coils thickness at microwaves/infrared wavelenght (micro-antenna), not at UV (nano-antenna).
    I read that the issue with Nantenna are technological 1. nano-structures difficult to manufacture 2. diods are too slow to produce direct current at high frequency

    If there is a crystal that absorbes UV and issue micro/infrared waves (luminescence) it should induce current in micro coils.
    I think it should be properly polarized to maximize the delta flux in the coil.

    I was wandering if someone of you know some research/article on this specific matter.
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