New Zealand Scientists Make Atom-Trapping Breakthrough 101
Mogster writes with this news from New Zealand: "'University of Otago scientists have made a 'major physics breakthrough' with the development of a technique to consistently isolate and capture a fast-moving single atom. A team of four researchers from the university's physics department are believed to be the first to isolate and photograph the Rubidium 85 atom.' Good to see Kiwis following in Rutherford's footsteps."
Not quite the best description of their work (Score:5, Informative)
What is important about this experiment is how often they can trap a single atom. Previous experiments have shown that creating a small trap volume and using atomic collisions allows for a 50% probability. (This is the regime our experiment is currently trying to work in) Their work showed that it is possible to exceed this using fairly simple techniques. There are also more complicated theoretical methods which various groups are trying to demonstrate as well. I believe they have reported >80% probability of loading a single atom into their trap. This increased probability is not completely necessary for scaling atomic quantum computers but will help. If they can achieve a probability close to 1 then this would help greatly. For instance with the old well established techniques I would make an array of 100 trapping sites but only expect to have 50 usable qubits loaded during any one experiment. This would now give us the ability to say we have more than 80 usable qubits for every experiment, which just helps scaling the quantum computer to useful sizes easier.
I would be quite surprised if this was the first time that single Rb 85 atoms had been trapped and imaged. We have been using single Rb 87 atoms in our experiments since about 2005 and other groups had been doing it before us. Switching to Rb 85 would take us about 15 minutes as the only required change is a frequency change of ~2 GHz for our two cooling lasers.
Re:Oh... (Score:5, Informative)
The good news is I went and found it, the bad news is it's probably not as cool as I'd hoped: http://www.scoop.co.nz/stories/ED1009/S00122/university-of-otago-atom-breakthrough-represents.htm [scoop.co.nz]
Re:Oh... (Score:5, Informative)
Photographs of trapped single atoms abound; they're just not that interesting. The atom will scatter light from the trapping beams and the scattered light can be easily imaged onto a camera. In fact, imaging is often used to characterize the trap. The atom just shows up as a blurry dot with the size of the blur being determined by the diffraction limit of the light or perhaps the tightness of the confinement. There's certainly no internal structure that would be resolvable.
Re:Oh... (Score:4, Informative)
I couldn't find an article to the original article, but this article has the picture that I was searching for anyhow, which shows a "net" of Germanium atoms on an ink blot.
Re:Possibilities for energetic particles? (Score:4, Informative)
The work is related to trapping single, neutral atoms efficiently. Trapping techniques for bulk quantities of charged particles tend to be simpler. Slowing down energetic particles is probably tough, but doesn't relate to this research.
Re:Is the photograph life size or something? (Score:5, Informative)
Re:Oh... (Score:5, Informative)
Speed of sound (Score:3, Informative)
FTFA: "Atoms usually move at the speed of sound, making them difficult to manipulate."
It's not quite as simple as that.
Sound [wikipedia.org] moves at the speed of sound, not atoms. Sound is a perturbation in the medium and is not always directly related with the speed of the particles. A simple experiment: bang a railroad rail with a hammer. The sound will travel at 6000 meters per second along the rail. Observe the rail: is it moving at 6000 m/s? I don't think so.
In a gas, [wikipedia.org] the statement about the typical speed of an atom being on the same order of magnitude as the speed of sound is correct, but the statement as written in the article is misleading.