NASASpaceFlight.com Forum
General Discussion => New Physics for Space Technology => Topic started by: DaCunha on 04/17/2016 11:57 am
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For those who are out there with enough time and money.
After a long online search in the scientific paper databases I am quite sure that the following
experimental configuration has never been investigated on this planet.
Irradiate a HT Superconductor disk like YBaCuO at 77 K perpendicular to it's circular surface
with a circulary, radially or azimutally polarized electromagnetic wave and/or a Laguerre-Gaussian
electromagnetic wave (orbital angular momentum quantum number l=1) with f < k*(92 K - 77 K) / h
(k: Boltzmann constant and h: Planck constant), in order not to exceed the binding energy of YBCO's cooper pairs.
E.g. high frequency microwaves.
Correct me if I am wrong, but I don't even think there has been a theoretical explanation of what will happen. If anyone can tell me, I would be glad to see a derivation. (Maybe just considering conventional SC's because there we have the BCS theory)
Unfortunately (but especially now I would be happy if you correct me because I am wrong) from an experimental point of view, while it is easy to produce laser beams carrying a polarization or phase vortex (i.e. radially polarized beams, azimutally polarized beams, Laguerre-Gaussian beams, respectively) using
a quarter wave retardation plate + CaCO3 crystal or a Spatial light modulator, respectively.
It is very difficult to produce suche vectorial beams in the low-frequency spectrum of EM waves, isn't?
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What spacecraft (SC's)?
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Sorry, I did not notice that SC is of course an ambiguous abbreviation in this forum.
Here: SC = Superconductor
I was inspired by the work:
https://arxiv.org/ftp/gr-qc/papers/0203/0203033.pdf
They considered an analogous effect as the Barnett effect (or inverse Einstein-de-Haas effect)
for the component of the gravitational field that has (in weak field limit) the same mathematical form as the magnetic component of an electromagnetic field.
In their experiment they argued, that because mechanical angular frequencies can't exceed some 10000 rpm. The corresponding effects can't be measured in a lab.
I however think, that it is not necessarily the mechanical rotation of the SC disc that is decisive but the overall angular momentum state of the condensate within the SC. This state, i. e. it's orbital angular momentum quantum number, might be manipulated by the irradiation of a phase vortex carrying electromagnetic wave.
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what would be the use for space travel?
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I do think it could be relevant:
The focus of a radially or azimutally polarized Microwave to Terahertz wave field below the critical frequency stated above would exhibit a longitudinal component of the electric or magnetic field vector respectively, oscillating with ( if you consider YBCO at 77 K) a frequency of up to ~ 200 GHz. and the latter would consequently induce cooper pair vortex currents that would oscillate with the same frequency . A similar effect should be observed by excitation with a Laguerre-Gaussian-mode of a certain sufficiently high orbital angular momentum quantum number l.
According to the work below, the gravitomagnetic field generated by a superconductor that is excited in such a way could be drastically amplified, as compared to the experiments that were all carried out with angular frequencies that are in the order of 100 to a couple of 1000 rpm.
https://arxiv.org/ftp/gr-qc/papers/0203/0203033.pdf
Since this experiment has not been done before. I think it would be a worthwile task.