from the kind-of-round-and-square-and-wavey-and-straight dept.
Physicists at the University of Basel have shown for the first time how a single electron looks in an artificial atom.
Controlling and switching [the spin of an electron] or coupling it with other spins is a challenge on which numerous research groups worldwide are working. The stability of a single spin and the entanglement of various spins depends, among other things, on the geometry of the electrons—which previously had been impossible to determine experimentally.
This is only possible in an artificial atom, so what, you may ask, is an 'artificial' atom?
A quantum dot is a potential trap which allows confining free electrons in an area which is about 1000 times larger than a natural atom. Because the trapped electrons behave similarly to electrons bound to an atom, quantum dots are also known as "artificial atoms."
This has potential application in quantum computing as electron spin is a candidate for use in storing quantum information.
More information: Leon C. Camenzind et al. Spectroscopy of Quantum Dot Orbitals with In-Plane Magnetic Fields, Physical Review Letters (2019). DOI: 10.1103/PhysRevLett.122.207701
Peter Stano et al. Orbital effects of a strong in-plane magnetic field on a gate-defined quantum dot, Physical Review B (2019). DOI: 10.1103/PhysRevB.99.085308.
(Score: 1, Insightful) by Anonymous Coward on Thursday May 23 2019, @08:55PM (1 child)
I wish I was knowledgeable enough to reply something meaningful but I am not. So I will just state that I enjoyed the article
(Score: 2) by sshelton76 on Friday May 24 2019, @12:05AM
I want to mod you insightful or touche but I'm unsure which is the correct response and also I'm out of mod points.
(Score: 2) by Freeman on Thursday May 23 2019, @09:16PM
They said they had the Quantum Dots, but no, it's just marketing speak.
https://en.wikipedia.org/wiki/Quantum_dot_display [wikipedia.org]
Otherwise knownw as Nano Crystal Displays:
https://www.highdefdigest.com/news/show/Samsung/CES/nanocrystals/suhd/Ultra_HD/4K/samsung-introduces-suhd-4k-displays-with-nanocrystal-technology/20339 [highdefdigest.com]
Joshua 1:9 "Be strong and of a good courage; be not afraid, neither be thou dismayed: for the Lord thy God is with thee"
(Score: 3, Informative) by coolgopher on Friday May 24 2019, @12:58AM (2 children)
Okay, I RTFA'd and I still don't know what the supposed geometry (I'm assuming it's a probability distribution field) actually is...
<clickety-click readity-read>
After clicking through the first "More information" link a bit further, I got this page [aps.org] where it suggests it's largely a slightly squashed sphere. However, the say
which is precisely what they found, which makes me slightly concerned that the result is biased. Still, it's a step forward, and if it's wrong, someone will have a good time proving it.
(Score: 0) by Anonymous Coward on Friday May 24 2019, @02:34AM
Experiment matched prediction, so I am inclined to believe it. Of course, they need to have at least 1 more prediction that does not match to properly demonstrate that they are right.
Yet, the red-blood-cell type looking electron makes me wonder why it is squished in one direction? Is it related to the direction of their measurement device?
(Score: 2) by hendrikboom on Friday May 24 2019, @05:51PM
Sounds like a pretty ordinary numerical strategy. Start with a guess, see where it leads, and keep changing it until convergence.
(Score: 2) by hendrikboom on Friday May 24 2019, @03:07AM
What does it even *mean* for an electron to have a shape?
(Score: 3, Informative) by maxwell demon on Friday May 24 2019, @06:51AM
They didn't determine the shape of an electron, they determined its distribution in the quantum dot.
And yes, this quote from one of the researchers didn't actually help:
Sorry, Loss, that's not putting it simply, that's putting it wrong. What you determined isn't what it looks like, but where you're likely to find it.
So what does it look like? Well, for the current experimental abilities, it looks like a point.
The Tao of math: The numbers you can count are not the real numbers.