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Levitating Graphene Is Fastest-Spinning Object

Posted by CmdrTaco on from the onesies-twosies dept.

techbeat writes "A flake of exotic carbon a few atoms thick has claimed a record: the speck has been spun faster than any other object, at a clip of 60 million rotations per minute. Previously, micrometre-sized crystals have been spun at up to 30,000 rpm using an optical trap. It is thanks to graphene's amazing strength that the flakes are not pulled apart by the much higher spinning rate, says Bruce Kane at the University of Maryland in College Park. Spinning could be a way to probe the properties of graphene, or manipulate it in new ways."

26 of 146 comments (clear)

  1. neat by Gnaythan1 · · Score: 4, Interesting

    can you give it enough mass to make it into a decent flywheel?

    1. Re:neat by sFurbo · · Score: 2, Informative

      It doesn't matter, the maximum energy stored per mass of flywheel is the specific tensile strength of the material. If the specks have higher specific tensile strength than the bulk, it would be more, though.

    2. Re:neat by N3Roaster · · Score: 2, Funny

      Obligatory xkcd

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    3. Re:neat by endymion.nz · · Score: 2, Informative

      Yes, it is better described by the conservation of angular momentum, but we all know what a centrifuge does.

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      mediocrity rules, man
  2. This is a great leap forward... by Anonymous Coward · · Score: 3, Funny

    ... in Dradle technology.

  3. uhm, 30 000RPM? by Skal+Tura · · Score: 3, Informative

    Summary fscked up. 30 000RPM isn't exactly much at all.

    Ie. almost all RC (radio controlled) model brushless motors can do 30k RPM, and some brushed motors can do that as well...

    Nevermind so many other things which do spin reaaally fast ...

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    1. Re:uhm, 30 000RPM? by Anonymous Coward · · Score: 3, Funny

      Isn't 30,000RPM where most Hondas need to be run in order to make any sort of usable power?

    2. Re:uhm, 30 000RPM? by nedlohs · · Score: 2, Insightful

      A brushless motor is not a crystal being spun in an optical trap.

      The world record for the 100m dash is 9.58 seconds. That an F16 could do it faster is irrelevant to that claim.

      Of course why they chose to mention that, given it isn't using the same technique, is a mystery. But they never claimed that was some kind of general spinning speed record.

    3. Re:uhm, 30 000RPM? by retroStick · · Score: 2, Informative

      It's not a typo, it's talking about rotations of a single microcrystal.
      The previous article that is referenced records rates of 500 rotations per second - which is 30,000rpm.

    4. Re:uhm, 30 000RPM? by mea37 · · Score: 2, Interesting

      If only they'd thought to attach their single microcrystal to a brushless motor...

    5. Re:uhm, 30 000RPM? by Beardydog · · Score: 2, Funny

      As a CRXologist, I can confirm this.

    6. Re:uhm, 30 000RPM? by tomhudson · · Score: 2, Informative

      Turbos regularly go into the 100,000+ rpm region.

  4. Video? by Yvan256 · · Score: 2, Interesting

    No wait, even if we have a video that ran at one million frames per second all we would see is an immobile object. At two million frames per second we would see it move instantly by 180 degrees...

    How did they calculate that 60 million rotations per minute again?

    1. Re:Video? by wjousts · · Score: 2, Informative

      So after RTFA(bstract):

      At micro-torr pressures, torques from circularly polarized light cause the levitated particles to rotate at frequencies >1MHz, which can be inferred from modulation of light scattering off the rotating flake when an electric field resonant with the rotation rate is applied.

    2. Re:Video? by vigour · · Score: 4, Interesting

      No wait, even if we have a video that ran at one million frames per second all we would see is an immobile object. At two million frames per second we would see it move instantly by 180 degrees... How did they calculate that 60 million rotations per minute again?

      They shoot a laser beam through the sample, which they measure with a detector at the other side. Then they apply an electric field to the flakes at high frequency (> 1 MHz). They scan the frequency of the electric field from 4 kHz up to 3MHz. When the frequency of the electric field is the same as the frequency of the rotating flake you get a resonance which appears as a sudden spike in the laser detector. That's how they know what the rotation rate is, and the dielectric response of graphite to an electric field is well known so they can cross check this with theory.

      ...and technically we do have video systems that can acquire data up to 1 peta Hz (or if you're american you'd say 1 quadrillion Hz). Femtosecond lasers are used in chemistry for more than a decade now to image fast chemical reactions.

      Hope this rambling post helps!

  5. That is impressive but not as interesting as... by Assmasher · · Score: 3, Funny

    ...when I watched an idiot EN3 (Petty officer 3rd class) walking on a prop shaft cover (which he knew he wasn't supposed to do) while we were under way and slipping and engaging the tiny tiny tiny tiny little gear that was intended to turn the shaft in port to avoid warping. I don't remember the ratio of the gear but it was something on the order of a few hundred thousand to one (it turned the shaft once every 90 minutes or something) and when this dipstick engaged it (someone was doing maintenance on it so it was unlocked) the shaft was doing 150 rpm or so. I remember doing the math at the time and figuring out the max RPM on the gear was somewhere along the lines of 35 million plus rpm. Now, the gear didn't make it that high since it disintegrating with what sounded like a bomb going off. Thank God it was small as it blew holes through bulkheads, steel covers, blew the cover off the rocker arms on the diesel engine 20 feet away. Nobody was hurt except for some ringing ears. Ahh, those 3 years in the Navy before I go to university, what things we learned... Hehe. BTW, the 'instant petty officer' was upside down in the reduction gear lube sump the minute we got back into port as punishment (the cheng [chief engineer] had him practicing his needle-gunning skills in the bilge two hours every morning in the meantime.)

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    1. Re:That is impressive but not as interesting as... by MachDelta · · Score: 3, Funny

      When I worked as a mechanic I once saw a crankshaft pully come off at speed. My co-worker was replacing a timing belt on an older for Escort and had a bit of trouble getting it lined up properly. When he figured it out he got all excited and hopped in the car without actually bothering to bolt the pully to the crank... so when he fired it up, and it worked, he got all excited and revved the engine a few times. This sped up the inevitable march of the pully down the end of the crank, where it ran out of room and fell off while doing about 4000rpm. It bounced twice in a shower of sparks, and the third time it "hooked up" and shot across the floor of the garage like a rocket. Needless to say, the engine died and the pully was now in more than one piece, as was the bit of wall it smashed into. My co-worker was devastated, but the rest of us were in stitches. :)

  6. Re:30k rpm = typo by Anonymous Coward · · Score: 4, Informative

    No typo. Read the original abstract: http://www.ncbi.nlm.nih.gov/pubmed/19424395

    500 turns per second. But your HD isn't put to rotation by a light beam - that's the news of this article, not the speed.

  7. Other elements by WalksOnDirt · · Score: 3, Interesting

    I wonder how fast you could spin a nitrogen molecule before it falls apart? It should be calculable. Would hydrogen go even faster?

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  8. Re:Reminds me ... by somersault · · Score: 4, Funny

    Next time you teach someone to drive a manual, don't let them touch the accelerator until they learn how to use the clutch..?

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    which is totally what she said
  9. Ultimate Tilt-a-Whirl by decavolt · · Score: 2, Funny

    Finally a material strong enough to build the ultimate Tilt-aWhirl

  10. Re:You know what else spins that fast? by roman_mir · · Score: 3, Funny

    at a cool million rotations per second, and given the friction coefficient of human skin is about 0.8, I'd say that you have no crotch left.

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    You can't handle the truth.
  11. Re:Reminds me ... by corbettw · · Score: 5, Funny

    And avoid girlfriends who think it's OK to twist and pull the stick shift violently, whether it's ready or not. Could be indicative of future, uh, problems.

    --
    God invented whiskey so the Irish would not rule the world.
  12. Macroscopic RPM Record by Bob9113 · · Score: 2, Informative

    "As a result, the flakes started spinning at 60 million rotations per minute, faster than any other macroscopic object."

    "Previously, micrometre-sized crystals have been spun at up to 30,000 rpm"

    Following through to the source of that quote:

    "Their short axis follows the direction of the linear polarization of the beam. In circular or elliptic polarization, the crystals are spontaneously put in rotation with a high speed of up to 500 turns per second. It is the first time, to the best of our knowledge, that such a result is reported for particles of the size of our crystals."

    So, if the 30,000 RPM crystal is interesting because it was a crystal, or because it was small, fine. But if they're saying that 30,000 RPM was interesting for large objects, ummm, turbocharger turbines spin at up to 150,000 RPM.

    That said; 60 million RPM is very impressive.

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  13. Re:You know what else spins that fast? by darthdavid · · Score: 3, Funny

    So basically, what you're saying is that your 'mom' is a trap?

  14. Re:Reminds me ... by BenFenner · · Score: 2, Insightful

    x2 this not being funny. It is 100% informative. This is exactly how you need to learn to operate a manual transmission. You don't use the throttle until you are good and smooth with the clutch. The engine's idle control will keep the engine running and the revs high enough to get the car started from a roll in 1st gear. The idle control valve will apply the "throttle" for you. Just enough. If you can get the car going using no throttle (entirely possible and very easy once you've learned to be smooth and mindful with your left foot) then you will be in much better shape to work the clutch when you are finally allowed by your mentor to use the throttle.