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Super fluidity of electron stripped Helium 4

  1. Mar 22, 2013 #1
    Hello, I am a physics newbie (more of a computer scientist) but I was wondering, if a quart of liquid helium 4 had all of its electrons stripped from it and was super cooled, could it still reach the super fluid state? And once reaching that state would it retain a charge attraction?

    The reason I am thinking about this is because a super fluid has no fluid resistance or viscosity. It will even flow up the sides of containers. Further more, it is extremely hard to contain and will flow through solids such as glass. However, if one could capture super fluid in a magnetic bottle.... it could be kept isolated in a continuous super fluid state and used for cool things. Like being accelerated
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  3. Mar 22, 2013 #2

    Vanadium 50

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    A quart of fully stripped helium would not be a superfluid. It would not even be a fluid. The closest word to describe what it would be might be "explosion".
  4. Mar 23, 2013 #3
    Like charges repel. Helium nuclei (i.e., electron-stripped atoms) are positive. Hence,helium nuclei would repel each other.

    It would take an extremely strong magnetic field to hold a gas made of nuclei together. I don't think it is possible with current technology, or technology in the foreseeable future, that can hold a significant mass of "electron-stripped" helium together for any significant amount of time.

    The super fluidity could not make such a fluid stable. Viscosity is not the same as electrostatic interaction. The nuclei gas would still be unstable even if it were to become a superfluid. The viscosity would be zero, but the electrostatic repulsion would be enormous.

    The electrostatic attraction that such a nuclei gas would have for near by electrons would be just as hard to control as the electrostatic repulsion. The "magnetic bottle" containing such a gas would be surrounded by neutral atoms with electrons and nuclei. The nuclei in the bottle would attract the electrons in the surrounding gas and repel the nuclei of the surrounding gas. Thus, the atoms of the surrounding gas would be torn apart. The electrons falling into the helium-nuclei gas would release large amounts of energy.

    As someone else stated, such a gas could best be described as an explosion. Even aside from the safety issues, the cost, time and manpower in such an experiment would be prohibitive. Maybe you could calculate or otherwise predict some interesting property of such a nuclei gas that would warrant the effort.

    Bose-Einstein condensates made of neutral atoms are interesting enough.
  5. Mar 23, 2013 #4


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    The question is nevertheless interesting. It is well known that charged bosons will show superconductivity. Obiously it is not realistic to observe macroscopic quantities of unbalanced charge nuclei. However one may speculate that the superconductivity of Helium nuclei might be observable e.g. in Helium under high pressure. Then the electrons will probably form a more or less homogeneous metallic background into which the nuclei are embedded. At sufficiently the crystalline order of the nuclei should break down and the nuclei should form a bosonic quantum liquid. I am pretty sure this has been elaborated to quite some detail, e.g. I found an article about metallic helium in the interior of jupiter:
    Lars Stixrude andRaymond Jeanloz.
    Fluid helium at conditions of giant planetary interiors PNAS 2008 105 (32) 11071-11075; published ahead of print August 6, 2008, doi:10.1073/pnas.0804609105
    And e.g. Neill Ashcroft has studied theoretically the superconductivity in metallic hydrogen and other light elements under high pressure.
  6. Mar 23, 2013 #5
    The material that you are describing isn't stripped of electrons. The material that you are describing is more like white dwarf matter. White dwarf matter has degenerate electrons.

    The dynamics of the material would be governed mostly by the degenerate electrons, not the degenerate nuclei. Most of the pressure associated with this material would come from the degenerate electrons, not the nuclei. At finite temperatures, the mean free path between electron-electron collisions would have to be much shorter than the mean free path between nucleus-nucleus collisions.

    At temperatures very close to absolute zero, white dwarf matter with helium 4 would be comprised of two fluids. The fluid that causes most of the pressure would be a Fermi-gas of electrons. I am not sure that the fluid associated with the helium nuclei would be a super fluid.

    Each helium nucleus in white dwarf matter would have to collide with many electrons before it collided with another helium nucleus. However, I suppose that in the limit of absolute zero maybe the nuclei could become a Bose-Einstein fluid.

    It would be hard to separate the properties associated with the nuclei fluid from the properties associated with the electrons. The material would definitely be metallic, in that the electrons would conduct electricity. However, the nuclei would hardly matter at all. White dwarf matter with helium nuclei would be very similar to dwarf matter with hydrogen nuclei. I serious doubt you could distinguish between white dwarf matter with helium nuclei from white dwarf matter with iron nuclei.

    I think that the OP was asking about a gas of bare helium-nuclei. I doubt that he was talking about white-dwarf matter. White-dwarf matter is interesting. Although not stable under earthly conditions, it would be more stable than the bare nuclei that he was talking about.
  7. Mar 24, 2013 #6


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    Well, at least the atoms of hydrogen are supposed to form cooper pairs and thus become superconducting too.
    The point seems to be that the gap between the valence and conduction band closes at much higher pressure in the case of helium than in the case of hydrogen.
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