FTA: "The Strontium atom appears larger than its true size because it was emitting light, and was oscillating slightly, over the course of the long exposure."
I believe the journalist misunderstood this point. Trapped ions do oscillate somewhat, but the amplitude should be way below the resolution of this imaging system. Most likely the finite spot size is due to the finite resolution and maybe some blooming from over-exposure.
It's a very accurate way of doing it though. You know exactly where the point source is and ... that it is as close to a point as you're going to get. I wonder if this has an application in optics?
Hehe yeah, but probably hideously expensive, and there are cheaper ways to get real point sources.
Quantum dots are a few nanometers in size (so << the wavelength that they emit) and you can get a solution of them from Sigma Aldrich for ~$500. People mix them into their samples and then use that to deconvolve the image/volume that they acquire.
Thanks for that, (I missed the comment in the article), because my skeptic-o-meter was maxing out. You can see the machining marks on the electrodes. There's even screws to be seen in the photo, which makes the 'atom' about the size of a largish dust particle, using a rough guess.
