Slashdot Log In
New Electron Microscope Shows Atoms in Color
Posted by
ScuttleMonkey
on Fri Feb 22, 2008 01:52 PM
from the say-cheese dept.
from the say-cheese dept.
Cornell's Duffield Hall has acquired a new electron microscope that is enabling scientists to see individual atoms in color for the very first time. While old electron microscopes can be compared to black and white cameras, this new scanning transmission electron microscope uses a new aberration-correction technology that is both more intense and allows for faster imaging speed. "The method also can show how atoms are bonded to one another in a crystal, because the bonding creates small shifts in the energy signatures. In earlier STEMs, many electrons from the beam, including those with changed energies, were scattered at wide angles by simple collisions with atoms. The new STEM includes magnetic lenses that collect emerging electrons over a wider angle. Previously, Silcox said, about 8 percent of the emerging electrons were collected, but the new detector collects about 80 percent, allowing more accurate readings of the small changes in energy levels that reveal bonding between atoms."
Related Stories
[+]
Science: New Neutron Scatter Camera to Detect Smuggled Nukes 125 comments
Researchers at Sandia National Laboratories in California are developing a new neutron scatter camera that they claim will be able to detect radiation through much more shielding and at much greater distances than traditional tech. "The neutron scatter camera consists of elements containing proton-rich liquid scintillators in two planes. As neutrons travel through the scintillator, they bounce off protons like billiard balls. This is where "scatter" comes into play -- with interactions in each plane of detector elements, the instrument can determine the direction of the radioactive source from which the neutron came. [...] Computers record data from the neutron scatter camera, and using kinematics, determine the energy of the incoming neutron and its direction. Pulse shape discrimination is employed to distinguish between neutrons and gamma rays."
This discussion has been archived.
No new comments can be posted.
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
Full
Abbreviated
Hidden
Loading... please wait.
Not color, false color. (Score:5, Informative)
Re: (Score:3, Funny)
size of atoms wavelength of visible light (Score:2)
Re:Not color, false color. (Score:5, Informative)
The image they show is impressive when you consider that each blob of color is actually an individual atom, and that they've identified exactly what kind of atom is at each position. In this case they were using it to analyze interdiffusion of atoms at an interface. As nanotechnology becomes more and more 'real' you can imagine how useful it will be to image nano-objects with atomic resolution and elemental discrimination.
Parent
Re:Not color, false color. (Score:5, Informative)
Not to get too technical here, but each blob is actually a column of atoms, as the specimen is wedge-shaped and certainly more than one atomic layer thick.
Electron energy-loss spectroscopy (EELS) has been combined with STEM imaging for several years at least, allowing similar sorts of images to be synthesized. The major contribution of this work is that they've modified the optics so that, even at 0.5 angstrom beam widths (and hence pixel sizes), they still get enough signal to the EELS detector to allow for EELS mapping and spectra acquisition for each of those pixels, giving direct bonding information about the particular portions of atoms probed by the beam. That means that the researchers can tell the difference between titanium atomic columns at different locations within the crystal, depending on the other atoms surrounding them.
Well, I suppose I did end up getting too technical.
IAATEL (I am a transmission electron microscopist)
Parent
Re: (Score:2)
Almost. Energy-loss spectroscopy in SEMs isn't new. (And I don't think it's new in STEMs, either, AFAIK.) The innovation is in the corrective optics, as you
Re: (Score:2)
This means that for each pixel in the image, they can determine what kind of atom is being measured. So they can generate false-color maps of atomic identity.
That's interesting. I guess this microscope will have lots of applications. At first thought - in semiconductors production, carbon allotropes and God knows where else.
Just look at the images in the article; you can clearly distinguish lanthanum from titanium, manganese, and manganese-lanthanum. From that list alone the mind boggles with potential applications.
Actually, it *is* real color. (Score:3, Interesting)
Re: (Score:3, Interesting)
Re: (Score:2)
Ahh Color... (Score:2)
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
Schrodinger's Fridge (Score:5, Insightful)
Re: (Score:3, Funny)
Re: (Score:2, Funny)
Re: (Score:2)
Re: (Score:2)
What would a single man use milk for? At three dollars a gallon it would be cheaper to feed them gasoline. The only time I have milk in the fridge is when there's a woman living there. And it usually turns into stinky cottage cheese before it's half empty.
Befor you ask, they're my daughter's cats. I got stuck with them when she moved to Ohio with her fiancee.
Re: (Score:2)
Re: (Score:2)
If you're this guy [olliesbargainoutlet.com], you never have to wonder about that question. (third paragraph)
And for the record, I worked with this guy for a time.
Re: (Score:2)
It is false color, but it wouldn't have to be. It's possible to probe individual atoms with visible light of different wavelengths using STMs.
Re:Schrodinger's Fridge (Score:4, Informative)
Parent
And, Of Course... (Score:2)
Proof at last... (Score:5, Funny)
Re: (Score:3, Funny)
So that is why the Hindenburg didn't use Helium.
tHE nEW sKITTLES? (Score:2)
Sorry, couldn't help myself. Marketing controls my mind. And yours.
No native CMY support? (Score:2)
Re: (Score:2)
Atoms don't have color! (Score:5, Insightful)
Re: (Score:2)
Re:Atoms don't have color! (Score:5, Funny)
Parent
Re: (Score:2)
absorption spectrum [google.com] and emission spectrum [google.com]. So no atom has one unique color, but may have a series of wavelengths of light that it can emit [rochester.edu], which our sight would perceive as a mix of red, green or blue wavelengths [uc.edu],
Re: (Score:2)
Microsoft Interview (Score:2)
Re: (Score:2)
B: Octarine
Correct answers they don't expect FTW!
Yow! (Score:3, Interesting)
Made in the USA (Score:2)
I lived there when I was in elementary school. More important, a certain warehouse store has its headquarters there. So I wanna know when I'll be able to pick up one of these STEMs at Costco!
What do the electrons "reflect" off of? (Score:2, Insightful)
Re: (Score:3, Interesting)
Re: (Score:2)
Re:What do the electrons "reflect" off of? (Score:5, Informative)
To a first approximation, 'heavier' atoms (higher atomic number) will scatter electrons more strongly, since they have more electrons. On an electron micrograph, heavy atoms show up as dark (absorbed/scattered alot of electrons), whereas lighter atoms show up as being bright (most electrons were transmitted).
I'm glossing over many details, of course. The important thing to remember is that the incident charged electrons are interacting with the charged electron density surrounding the atoms in the material.
Parent
Re: (Score:3, Informative)
Ah, the evil remnants of a flawed basic chemistry and/or atomic physics class.
Just FYI -- not that it relates to this article -- this is wrong. So far as we know, an electron is a point particle, and the electrons in an atom aren't any different from a free electron. They are a collection of little points located at various definite positions. There's no "fuzziness" and they aren't "smeared out" in any sense at all. The "fuzzy cloud"
Next up (Score:2)
Real Harmonic Color (Score:4, Interesting)
Or maybe the color should be derived from the "texture" of the atom, just like the actual color of macroscopic materials. If a carbon atom has 12 electrons evenly distributed around a sphere in shells (2, 8 and another 2 in valence), let's see it get colored accordingly. Maybe the inner shell's diameter harmonic color in the visible range, divided by 2 and scaled back into the visible, overlapped with the same algorithm for the outer 8 in the second shell, then again for the 2 in the outermost shell.
The point is that these colors can mean something. And since the number and combination of electrons is so important to the characteristics of the electron, as well as offering the femtoscopic equivalent to macroscopic colored surfaces, I'd like to finally see what I've been imagining since high school chemistry class.
Screenshot (Score:5, Funny)
.
There's a nice AFM technique which does this too (Score:2)
Re: (Score:3, Insightful)
After all, an atom is smaller than a wavelength of visible light, so atoms are quite literally colorless.
Re:This thread is useless without pics! (Score:5, Funny)
Parent
Re: (Score:2)