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Levitating Graphene Is Fastest-Spinning Object 146

Posted by CmdrTaco
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."
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Levitating Graphene Is Fastest-Spinning Object

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  • neat (Score:5, Interesting)

    by Gnaythan1 (214245) on Thursday September 30, 2010 @11:36AM (#33747806)

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

    • by zrbyte (1666979)

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

      More precisely, you mean its moment of inertia [wikipedia.org]. It'll make a decent flywheel, if it has low moment of inertia but very high velocity, since the product of these two is what counts.

      In this case if you increase the mass (thereby increasing the moment of inertia) the system will just tare itself apart due to centrifugal forces. The thing here is that they could make it spin really, really fast because graphene is very light. For one it is made up of a single sheet of graphite (2D crystal) and graphite itself

      • Ok, I was with you until I read the word "centrifugal"... I was under the impression that science left that word behind long ago for "centripetal". At least that's what we were taught in the 80's. Has it come back in fashion to use it?

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

      no problemo [nrao.edu]

    • Im sure there are corpses spinning in their graves faster than this.

      Can we use them as flywheels?
    • by shentino (1139071)

      Even electrical signals, which move at close to the speed of light, have to be sent on smaller and shorter pathways in modern chips to get speedups.

      They run at gigahertz speeds, which implies nanosecond timings. A flywheel with decent mass spinning a million RPM is only four orders of magnitude away from the speed of light.

      • by Nyh (55741)

        They run at gigahertz speeds, which implies nanosecond timings. A flywheel with decent mass spinning a million RPM is only four orders of magnitude away from the speed of light.
        It all depends.

        Speed of light: 300e6 m/s
        Speed of micrometer scale graphene flakes spinning at 60 million rpm:
        2*pi*1e-6/1e-6 = 6 m/s = 21.6 km/h
        I think you can get any material spinning at 60 million rpm at micrometer scale. Tensile strength is not very important at these speeds.

        It is a nice trick though.

        Nyh

  • ... of trying to teach the GF to drive a stickshift back in high school. Went through a few clutches back then.
    • by somersault (912633) on Thursday September 30, 2010 @11:59AM (#33748124) Homepage Journal

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

      • by corbettw (214229) <corbettwNO@SPAMyahoo.com> on Thursday September 30, 2010 @12:48PM (#33748814) Journal

        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.

      • by jeffmeden (135043)

        This isn't as funny as it is practical. Any manual transmission car with a decent idle control system can be driven without touching the gas pedal given the clutch is used gracefully. Trying to teach someone how to drive a manual car via "gas in, clutch out" is a sure way to simultaneously fail to teach them the right way to drive, and ruin your clutch.

      • Re: (Score:2, Insightful)

        by BenFenner (981342)
        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 m
      • by Gilmoure (18428)

        Yup, an old uncle taught me and my cousins how to use the clutch by getting us to hold his truck on a slope using just the clutch and then being able to go forward and backward with the clutch. Fun stuff.

        • by inanet (1033718)

          while I've certainly driven cars with the right level of torque (especially diesel turbo utes with huge torque figures... had one that could do 30kph in first without touching the accelerator)

          this is not a rule. this is not 100% informative, i would pay money to anyone who could have done anything but stall my last car without giving it a little throttle, and it had a very powerful motor.

          but also an exceedingly heavy triple clutch. (to be fair _everyone_ who got in that car stalled it the first time they tr

          • by Gilmoure (18428)

            A buddy had a '67 Corvair that had been a NASA camera platform for filming planes landing. The roof was chopped off, a 327 small block was installed in the back seat and a plywood platform on top of the engine.

            You could have the car in 4th gear and let off the clutch too fast and it spin the tires. So much torque in such a light car!

  • Could this material be used to make HYPER MEGA TERRIBLY ASTRO FAST harddisks?
    • by Pojut (1027544)

      No, but it could be made to create indestructible ballet dancers.

      Think of it. No more sprained ankles...no more broken toes...it would revolutionize the culture!

      • No, but it could be made to create indestructible ballet dancers.

        Think of it. No more sprained ankles...no more broken toes...it would revolutionize the culture!

        Yeah, but people will still be unable to agree which way her silhouette [about.com] is spinning!

  • by Anonymous Coward on Thursday September 30, 2010 @11:43AM (#33747894)

    ... in Dradle technology.

  • uhm, 30 000RPM? (Score:4, Informative)

    by Skal Tura (595728) on Thursday September 30, 2010 @11:45AM (#33747922) Homepage

    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 ...

    • Re: (Score:3, Funny)

      by Anonymous Coward
      Isn't 30,000RPM where most Hondas need to be run in order to make any sort of usable power?
    • Blame New Scientist, the typo is there and was just quoted verbatim. Although there really should have been some basic sanity checking before it hit the front page (perhaps as a snarky "30,000 RPM? Really" footnote), I've long since learned not to expect such feats from the editors.
    • Re: (Score:3, Insightful)

      by nedlohs (1335013)

      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.

    • Re: (Score:2, Informative)

      by retroStick (1040570)
      It's not a typo, it's talking about rotations of a single microcrystal.
      The previous article [nih.gov] that is referenced records rates of 500 rotations per second - which is 30,000rpm.
      • Re: (Score:3, Interesting)

        by mea37 (1201159)

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

        • by mea37 (1201159)

          I guess I shouldn't complain, but I have to wonder why my dumbest jokes are getting mods like "Interesting" lately... This is worrying.

    • Re: (Score:3, Informative)

      by tomhudson (43916)
      Turbos regularly go into the 100,000+ rpm [clubwrx.net] region.
    • by treeves (963993)
      IIRC, my Dremel tool (which has a brushed motor) can do 30,000 RPM. I expect dental drills can go even faster.
  • They make 20k rpm hard drives. I'll bet that is a typo for 30k rpm. I'll bet it should be 30M rpm.
    • by Yvan256 (722131)

      or maybe 30k RPS?

    • Re:30k rpm = typo (Score:4, Informative)

      by Anonymous Coward on Thursday September 30, 2010 @11:54AM (#33748052)

      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.

      • by Paul Rose (771894)
        Mod parent up The summary and article were correct, but a bit confusing. 30,000 RPM was the record for spinning a crystal with light, not an overall RPM record.
  • Video? (Score:3, Interesting)

    by Yvan256 (722131) on Thursday September 30, 2010 @11:47AM (#33747948) Homepage Journal

    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?

    • by wjousts (1529427)
      Obviously you don't observe it with a video camera! Without bother to RTFA, I'd guess something like a femtosecond laser used.
      • Re: (Score:3, Informative)

        by wjousts (1529427)

        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.

    • My guess would be that they calculate based on measuring the amount of energy input into the system and subtracting what is observed escaping.

      I bet if I read TFA that would eliminate the need to make guesses, but this is slashdot.

    • Re:Video? (Score:5, Interesting)

      by vigour (846429) on Thursday September 30, 2010 @12:21PM (#33748392)

      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 [wikipedia.org] 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 [wikipedia.org] (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!

    • From the abstract linked above:

      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.

    • Rain Man.

    • by Khyber (864651)

      The same way they calculate rotations in a Dynaflex powerball, albeit on a larger and more precise scale.

  • So that's what a Warlock's Wheel has to be made of...
  • ...and I say it has to spin!
  • politicians can't wait for this technology to become usable.

  • by Assmasher (456699) on Thursday September 30, 2010 @11:52AM (#33748030) Journal

    ...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.)

    • by MachDelta (704883) on Thursday September 30, 2010 @12:15PM (#33748312)

      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. :)

  • Other elements (Score:4, Interesting)

    by WalksOnDirt (704461) on Thursday September 30, 2010 @11:55AM (#33748056)

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

    • According to Wikipedia, the dissociation energy of N2 is about twice that of H2 (http://en.wikipedia.org/wiki/Bond_dissociation_energy), but it weighs seven times as much. So unless the two N atoms are significantly closer together (I was unable to quickly determine their distance), it would seem the H2 molecule could spin faster than the N2 molecule. (I'm assuming they would dissociate when the rotational energy exceeds the dissociate energy.)
  • by Anonymous Coward

    In Romania they have a saying: Go spinning around.

    It roughly means go f*** yourself.

  • The speed makes me think of what would happen to a rotating sphere that spins so fast the outer portions become relativistic and undergo both spatial and temporal changes relative to the inner core.

    • The speed makes me think of what would happen to a rotating sphere that spins so fast the outer portions become relativistic and undergo both spatial and temporal changes relative to the inner core.

      The abstract says that the graphene is micron sized, so

      v = PI*D*w

      D = 1E-6
      w = rotational frequency = 1E6 Hz

      v = 3 m/s

      Sadly, not relativistic.

  • A 10-km diameter neutron star rotating in a millisecond is moving 30,000 km per second at the surface. That is tenth light speed and relativistic effects must be considered. "Neutron star" is just a name. The actual composition may be a quark soup, i.e single mega-nucleus. The attractive strong-nuclear & gravitational forces versus the repulsive centripedal and electrostatic forces are near unimaginable.
    • Can you cite something for this? The highest spin rate I could find for a neutron star (XTE J1739-285) [wikipedia.org] is 1122 times a second and it seems that it may not even be the correct rate.
      • The wiki reference mentions stars 12KM in diameter and "several hundred times a second". You mentioned almost 900 times a section. I'd consider one percent light speed to be highly relativistic. Some of these numbers are as much as ten percent.
      • Your finding validates the GP's comment:

        10 km diameter * PI ~= 30 km at the equator

        (30 km / rotation) * (1122 rotations / second) ~= 30,000 km / second ~= 10% * c

        Perhaps you were thinking of rotations per microsecond?

      • by ceoyoyo (59147)

        1122 times a second sounds like one rotation in something less than a millisecond, no?

      • by qmaqdk (522323)

        Can you cite something for this? The highest spin rate I could find for a neutron star (XTE J1739-285) [wikipedia.org] is 1122 times a second and it seems that it may not even be the correct rate.

        http://en.wikipedia.org/wiki/Pulsar [wikipedia.org]

  • Finally a material strong enough to build the ultimate Tilt-aWhirl
  • As noted by another poster, 30000rpm isn't a record. In my field of solid-state nuclear magnetic resonance, magic-angle spinning rotors can achieve 70kHz--or 4.2M rpm. Samples of 1-30mg of microcrystalline protein (or other sample) are spun in rotors of microliter volume using dry air : bearing gas to create a bed of air for the rotor, and a drive gas to propel the rotor. Spinning the sample suppresses anisotropic magnetic fields in the sample and simulate solution-like conditions.
  • Would it be simpler to use a sheet of graphene to build a space elevator rather than carbon nanotubes? It certainly seems to have the tensile strength for it...
  • My understanding is that it is graphite if there's more than one layer and it is only graphene when it is a single layer, which by definition is also a monatomic layer. If this is correct, then you cannot have graphene a few atoms thick. That has no meaning.

  • Sure, as many have pointed out, the 30K RPM using an optical trap might be a bit ambiguous, but this

    Kane then set them spinning using a light beam that is circularly polarised, meaning it passes its momentum to objects in its path.

    was really helpful - I'd always wondered what "circular polarization" meant.

    • That's completely wrong, actually. Light always applies some momentum to what it hits, the difference with circular polarised light is that it imparts a spin.

      Linear polarised light is the sine-wave shape you've probably seen before, circular polarised light is essentially a spiral around the direction of travel. See: http://en.wikipedia.org/wiki/Circular_polarization [wikipedia.org]

      It's used in 3D cinema glasses because there are two kinds of circular polarized light (referred to as left and right handed), which spiral opp

      • Perhaps the title "Science writing at its finest" was one of them "clue" thingies...
        • Oh, this internet sarcasm thing. Sorry, I just thought you were stupid.

          • No worries, most days I am stupid; but finding non sequiturs in New Scientist articles is like shooting fish in a barrel. If you want to have fun with stupid, though, check out the "citation needed" on the section "The axes of the ellipse have lengths (square root of 1 plus/minus sin (2 theta)...)" of the Elliptical polarization [wikipedia.org] article. Seems like every time I go to Wikipedia I find some forehead-slap inducing visit from some idiot sprinkling "citation needed"s around like it was pixie dust.
  • by Bob9113 (14996) on Thursday September 30, 2010 @12:54PM (#33748934) Homepage

    "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.

  • Sorry I can't find the source... but someone commented humorously that "Hertz has a unit named after them, why doesn't Avis?" Avis was semi-sarcastically named as a unit of angular velocity; 1 Avis is 2*pi radians of rotation per second, or 1 full rotation per second.

    So this is 1 million Avis.

  • std commercial ultracentrifuges, used in the life sciences, spin at 80 to 100 K, and the objects they rotate ("rotors" in the argot)are titanium cylinders or frustrated cones that weigh several kilos. Centrifgues that went up to 50K were available in the 1970s, if not earlier; one limit was the strenght of hte "rotor", which were made of aluminum at the time; now they are made of Ti and carbon fiber. As you can imagine, the manufacturers are carefull to stress safety; one thing that distinguishes a Beckman
  • Its University of Maryland, College Park

    It is the University of Maryland

    UMBC, UMES, and UMUC may share the 'University of Maryland' name, but are in no way related beyond the fact their state owned.
  • Is it true that relativity predicts that rotating an object increases its mass? Does this graphene apparatus offer a way to test that theory, as the starting mass is small enough to detect small increases as large relative to the starting mass, and the rotation can be high enough frequency to really see the effects of the phenomenon?

  • WolframAlpha needs to be updated now. Did a search on 60 million rotations per minute to find out the period (1×10^-6 seconds), and I noticed this bit of info: ~~ 3 × fastest induced angular velocity (steel ball 0.8 mm diameter suspended in vacuum) (~~ 2×10^7 rpm )

    60 million rotations per minute - Wolfram|Alpha [wolframalpha.com]

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