Whether wielded by Egyptian sun gods, Luke Skywalker, or your run of the mill solar-thermal power plant, light has the potential to do big things. Thanks to a breakthrough by UC Berkeley and the DOE's Lawrence Berkeley National Lab, we can now make light do very small things as well. Researchers there have created the first nano-sized light mill motor that can be manipulated in both speed and direction by tuning the frequency of the light waves that serve as its power source.
The plasmonic motor is only 100 nanometers in size, but given the right kind of power in the form of a linearly polarized light beam, it can produce enough torque to turn a silica disk 4,000 times larger than the motor itself. This type of light-driven motor isn't new, but the kind of power derived from a motor this small is unheard of up to this point. Previous attempts at plasmonic motors required the devices to be at least many micrometers in size, and even then they produced far less torque per unit volume.
The breakthrough is in the gammadion gold structures that make up the motor. The gammadion structure's symmetry coupled with the way it interacts with all incident light – not just light coming in from a particular angle – a simple linear polarized beam can coax a great deal of torque from the motor. That increased interaction between light and gammadion structures spells more power from less motor.
The motor is also sensitive to wavelength, which can be used to change the direction of the motor. As you can see (sort of) in the video below, a shorter wavelength of 810 nanometers gets the motor humming in a counterclockwise direction. A similar beam at 1,700 nanometers gets it cranking in the opposite direction.
Such tiny, controllable light-powered motors could have myriad biological applications, not least of which is manipulating DNA in vivo, using the motor to unwind and rewind a double helix. They could also lead to improved nanoelectromechanical systems and better solar harvesting devices.
Why does it look like a swastika?
The swastika is an ancient symbol used by many different cultures. It's a shame the nazis managed to hijack it and stigmatize it for the rest of human existence.
it looks like a swastika because your a nazi! jk, but yeah before it was used by the nazi party in germany and most of europe, it was known as, ironically, a symbol of peace.
engineering standpoint it looks like a swastika because it is actually a good setup for a windmill shape. great idea, this may finally bring about nano machines fixing spaceships!
Nano Nazi! wow.
They could have used the mirror image of the swastika, instead of the swastika itself. Wouldn't that have had the same properties? It would be less distracting, at least.
that is the mirror image of a swastika.
What freaked me out is my high school had swastika's throughout the tiling on the floor in the entranceway. It was built a century ago when progressives ruled the world. They loved that kindof eugenic'y thing then. Uh and kindof now though we drove them underground a bit with just coming out and saying it. Now they just make policy and try to subtly convince people through media that they deserve death. You are a virus that is destroying mother earth and need to accept destruction.
Ahh the more things change, the more they stay the same.
the nazi swastika is just a mirror image of the real swastika
It's a pretty simple shape, a lot of cultures have used one or both to mean various things. :P The only reason we don't still have that reaction to 'the rising sun' is that hating circles is just too silly.
And I thought the group of bald men who beat the crap out of me in the park were white supremacists, turns out they were scientists. Who funds those guys anyways?
It's my belief that the swastika was once a world-wide known name for what the Hebrews believed was the one true God. In support of this belief I submit the following arrangement of the tetragrammaton arranged circularly from the top to the left counter-clockwise.
And what's more, the Hebrew definition for the tetragram, is the causative form of the verb meaning 'to be'.
The actual swastika has the same meaning....
That and it's used as a symbol in Buddhism as well. It was a good thing there too, but most people wouldn't be bothered to see the difference.
guys ignore the fact its a sign of a past empire and look at the idea itself this could mean all sorts of cool stuff mini screw drivers and drills or even pumps we could use this tech for lots of cool stuff and maby take away the stigma around the symbol.
This is a natural extension of the laser pulse powered aerial vehicle. Now I'm thinking laser driven miner bots. Mining would be so much more profitable if the miners could work the vein rather than having to make the environment safe for humans as a primary directive.
amazing how even in a science focused environment people still rather comment on the irrelavent parts of the subject. what about the relavence of why we would want to rotate a motor with beams of light?