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Phenomenon Discovered In Ultracold Atoms Brings Us a Step Closer To Atomtronics
An anonymous reader writes "A new phenomenon discovered in ultracold atoms of a Bose-Einstein condensate (BEC) could offer new insight into the quantum mechanical world and be a step toward applications in 'atomtronics'—the use of ultracold atoms as circuit components. Researchers at the National Institute of Standards and Technology have reported the first observation of the 'spin Hall effect' in a cloud of ultracold atoms, acting as a single quantum object and then called BEC, the lowest state of matter, with solid and liquid coming next. As one consequence, the researchers made the atoms, which spin like a child's top, skew to one side or the other, by an amount dependent on the spin direction."
I'm just gonna pretend i'm totally comfortable with the subject matter and i've understood it all perfectly when i'm gonna talk to my friends about the latest and greatest science news.
I'm gonna look oh so smart.
I'm not even going to pretend I understand how this would work, but I doubt anyone but those with the deepest pockets could afford an ultracold computing device.
Agreed. When it's not completely wrong, it still manages to be deftly incoherent.
The atoms don't physically spin. Spin is just a word used, in the absence of a more appropriate one, to communicate an inherent quantum mechanical property of atoms. Spin is closely related to magnetism.
What do you mean by "physically spin"? They have angular momentum and behave in a way that is almost always consistent with them physically spinning. The classical description of nuclear spin is as useful as the Newtonian description of motion.
If you want to be pedantic, go all the way. There aren't really atoms, particularly not in a Bose-Einstein condensate, just excitations of particular fields.
You can actually do an experiment that macroscopically results in true spinning of a cylinder due to aligned little spins. I can't find a reference. Anyone recall?
The atoms don't physically spin. Spin is just a word used, in the absence of a more appropriate one, to communicate an inherent quantum mechanical property of atoms.
Angular momentum at the subatomic level is the same thing as angular momentum at the macro level. Conservation applies. It's weird, it's not intuitive, but it's physical reality. It has commercial applications, too, such as NMR and MRI. Feinman's "QED" has a good explanation.
Just imagine it in William Shatner's voice.
No, if you're in doubt, read a few comments. You should see a pretty good mixture of "ARM is killing Intel!", "Intel is killing ARM!", "Why doesn't AMD make better stuff these days?", "Intel is a convicted monopolist!" and "Why don't we have low-end hexa-core processors yet?" comments.
I thought Disney World mastered that stuff years ago.
Spin is closely related to magnetism.
The spin of charged particles gives them a magnetic moment (i.e., they have north and south magnetic poles). The spin of neutral particles, not so much.
In Coursera's recent "Exploring Quantum Physics" class, Ian Applebaum talked about spin. If electrons spin like tops spin, you can calculate the minimum speed it must be spinning from the electron's charge, size, and magnetic field. The problem is that the minimum speed exceeds the speed of light.
More at http://www.askamathematician.com/2011/10/q-what-is-spin-in-particle-physics-why-is-it-different-from-just-ordinary-rotation/
Slashdot title says we are a "Step Closer To Atomtronics". Nevevermind that TFA says "that it is unlikely to be a practical way to build a logic gate"...