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  • I have got some mega news for you, my friends, and it involves two of our favorite words:

  • graphene and superconductors.

  • Let's just dive right in, shall we?

  • To understand this latest news, we have to go back to last year.

  • The physics world was sent into a tizzy by the discovery of a 'magic angle' in graphene.

  • Now, graphene is a single-atom thick layer of carbon that forms a hexagonal lattice pattern,

  • and its atomic arrangement gives it certain exciting properties, like being over 200 times

  • stronger than steel, flexible, transparent, and highly conductive.

  • This last property was highlighted in 2018 when researchers put two layers of graphene

  • on top of each other, and twisted them at exactly 1.1 degrees.

  • They cooled the graphene structure to just above absolute zero, applied a strong electric

  • field, and found that not only are these graphene bilayers highly conductive, they exhibit

  • alternating areas of conductivity and insulation.

  • So in some areas, they saw graphene bilayers with a twist to behave like a superconductor.

  • That means there's no resistance to an electrical current and therefore, the current can flow

  • super efficiently.

  • But here's the kicker: we don't know why!

  • We don't fully understand what's happening at the molecular level to make this particular

  • orientation of graphene capable of superconduction And this year, in further exploring the capabilities

  • of this seemingly 'magical' twist, scientists have now discovered something that is arguably

  • an even bigger deal.

  • An international team at the Institute of Photonic Science in Barcelona 'cleaned up'

  • the experiment.

  • They made what they call 'magic-angle twisted bilayer graphene devices', a name that will

  • never get old for me.

  • Essentially, they took these two stacks of graphene rotated at the magic angle, and used

  • a mechanical squeezing process to eliminate impurities.

  • This squeaky clean version of the experiment allowed them to see details they hadn't

  • before like the device's incredible versatility.

  • It turns out, graphene stacked and turned at the magic angle can be tuned to act as

  • many things.

  • Depending on the charge running through it, the experimental setup could act as an insulator,

  • a superconductor, or even a magnet!

  • And j

  • ust by changing the current running through the device, scientists could turn

  • states on and off, which is exciting for many reasons.

  • It could make these materials really useful inside electronics, as they're controllable

  • in much the same way our current electronics are: they're tunable.

  • But this new research is also a step toward solving the mystery of exactly how this happens.

  • Work like this lets us explore and manipulate the microscopic world inside graphene devices,

  • allowing us to better understand how this material works and how we can use it.

  • In addition to furthering our existing understanding of how these bilayer graphene stacks behave,

  • the team was able to beat the record temperature at which the material behaves as a superconductor.

  • And this is incredibly important, as our existing ways of inducing superconducting behavior

  • in most materials requires extremely low temperatures and/or high pressures.

  • Superconductors would be so useful if they didn't require such low temperatures to

  • function.

  • And in the field of physics, discovering or creating a room-temperature superconductor is considered

  • something of a holy grail.

  • This most recent graphene work has demonstrated that graphene magic angle bilayer devices

  • can act as superconductors at a temperature above 3 Kelvinwhich, while not the warmest,

  • is the highest temperature ever demonstrated for a graphene superconductor.

  • Along with graphene's other tantalizing properties, achieving superconductivity at

  • easier-to-maintain temperatures could be seriously useful in many future applications.

  • Things like incredibly efficient power transfer, hovertrains, or even quantum computing.

  • But that future can only really become a reality if we develop a better understanding of the mechanisms

  • of action at play, and can use that understanding to improve the performance of 'magic' materials like this.

  • What are your thoughts on graphene and its many 'magical' properties?

  • Let us know down in the comments below, and for more on superconductor breakthroughs,

  • check out this video over here.

  • Subscribe to Seeker to stay up to date with all new materials science discoveries, and

  • thanks so much for watching. I'll see you next time.

I have got some mega news for you, my friends, and it involves two of our favorite words:

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B1 中級

魔法 "角度石墨烯回來了......有了更大的變化。 ('Magic' Angle Graphene Is BACK...with an Even Bigger Twist)

  • 3 2
    林宜悉 發佈於 2021 年 01 月 14 日
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