New test of hydrogen sulfide backs up superconducting claim

New test of hydrogen sulfide backs up superconducting claim
Pressure and temperature effects on Tc in sulfur hydride and sulfur deuteride. Credit: arXiv:1506.08190 [cond-mat.supr-con]
(Phys.org)—A combined team of researchers from the Max Planck Institute and Johannes Gutenberg University, both in Germany has backed up the findings of prior research indicating hydrogen sulfide becomes a superconductor at high pressure and a temperature of 190K. In their paper they have uploaded to the preprint server arXiv, the team describes their latest experiment and what it might mean for eventually finding a superconductor that works at room temperature.

Ever since 1986 following the discovery of superconductivity in cuprates, which showed that superconducting materials could be made, scientists have been looking to find one that would work at room temperature—should they succeed it would revolutionize electronics. Up till now, progress has been constant but no material has been found that could be used in everyday products. Last December, a team with some of the same members as this new group, announced that they had found that putting hydrogen sulfide under (150GPa) caused it to exhibit signs of being a superconductor at 190K—but they were not able to get it to demonstrate the Meissner effect—where a material expels a magnetic field—a key test of a superconductor. In this new effort, the researchers tested a sample in a different way, and this time, did get it to demonstrate the Meissner effect.

To make it happen, the team built a non-magnetic cell and used an ultrasensitive SQUID magnetometer. A tiny sample of was then exposed to two million atmospheres of pressure while the temperature was raised very slowly from just above absolute zero—at 203K they got their magnetization signal indicating that the material did indeed demonstrate the Meissner effect.

The researchers propose that the reason for the is vibrations in its crystal lattice which occur due to compression. If that turns out to be the case, other hydrogen materials might be as well, perhaps at different temperatures, some maybe as high as . As to why there was a small temperature difference this go round, the team suggests it was likely due to differences in crystal structure between the samples used in this latest effort versus that used last December.


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More information: Conventional superconductivity at 203 K at high pressures, arXiv:1506.08190 [cond-mat.supr-con] arxiv.org/abs/1506.08190

Abstract
A superconductor is a material that can conduct electricity with no resistance below its critical temperature (Tc). The highest Tc that has been achieved in cuprates1 is 133 K at ambient pressure2 and 164 K at high pressures3. As the nature of superconductivity in these materials has still not been explained, the prospects for a higher Tc are not clear. In contrast, the Bardeen-Cooper-Schrieffer (BCS) theory gives a guide for achieving high Tc and does not put bounds on Tc, all that is needed is a favorable combination of high frequency phonons, strong electron-phonon coupling, and a high density of states. These conditions can be fulfilled for metallic hydrogen and covalent compounds dominated by hydrogen4,5. Numerous calculations support this idea and predict Tc of 50-235 K for many hydrides6 but only moderate Tc=17 K has been observed experimentally7. Here we studied sulfur hydride8 where a Tc~80 K was predicted9. We found that it transforms to a metal at pressure ~90 GPa. With cooling superconductivity was found deduced from a sharp drop of the resistivity to zero and a decrease of Tc with magnetic field. The pronounce isotope shift of Tc in D2S is evidence of an electron-phonon mechanism of superconductivity that is consistent with the BCS scenario. The superconductivity has been confirmed by magnetic susceptibility measurements with Tc=203K. The high Tc superconductivity most likely is due to H3S which is formed from H2S under its decomposition under pressure. Even higher Tc, room temperature superconductivity, can be expected in other hydrogen-based materials since hydrogen atoms provide the high frequency phonon modes as well as the strong electron-phonon coupling.

Journal information: arXiv

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Jul 02, 2015
If true than that would be a pretty big jump in temperature (I thought the current record was 150K or so)

At that temperature it would already work in a shadowed moon crater without any active cooling.

Jul 03, 2015
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Jul 03, 2015
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Jul 03, 2015
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Jul 03, 2015
You forgot the 2 million atmospheres......

Jul 04, 2015
This probably an ignorant question but if molecules shrink at really low temps and you get superconductivity at those temps and now they are finding you can get it at higher temps if you also highly pressurized them meaning your technically forcing the molecules to shrink could superconductivity simply be a condition molecules exhibit when they are shrunk below a crtain percentage of normal with all the individual parts of the molecules closer together? I know, off the wall but it does follow a certain simple logic...

Jul 04, 2015
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Jul 04, 2015
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Jul 04, 2015
It may be possible to make a solid structure with microchannels to contain these materials and form a superconducting coil.

KBK
Jul 05, 2015
It is interesting to note that sulfonated hydrogen bonds are directly implicated in the 12,000 year old sciences of the philosopher's stone, or 'the white powder of gold'.

And that the scientific claim is that the nanodust of the white powder IS stated as being superconductive, as measured by modern scientific gear.

If one is to respond to my voiced thoughts, here, they'd better know what I speak about to have deeply researched the hidden face of alchemy, hidden from public knowing.., before replying.

If not, they'd be an illiterate blowhard, who just might be trying to keep the public from knowing...or doing the work for those who try and keep it hidden.'

Remember, engineering has laws, so builds don't kill people. It must exist as dogma.

Science has only theory and is wholly subject to change at any moment. It must never exist as dogma, or it would be a violently enforced dead end.

Never, ever.....conflate the two. Unless you are illiterate, or a shill.

Jul 05, 2015
From the article;
The pronounce isotope shift of Tc in D2S is evidence of an electron-phonon mechanism of superconductivity that is consistent with the BCS scenario. The superconductivity has been confirmed by magnetic susceptibility measurements with Tc=203K. The high Tc superconductivity most likely is due to H3S which is formed from H2S under its decomposition under pressure.


Wow. Nice work. I'm suitably impressed.

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