The First X-Ray Taken of a Single Atom

An anonymous reader quotes a report from Ars Technica: Atomic-scale imaging emerged in the mid-1950s and has been advancing rapidly ever since -- so much so, that back in 2008, physicists successfully used an electron microscope to image a single hydrogen atom. Five years later, scientists were able to peer inside a hydrogen atom using a "quantum microscope," resulting in the first direct observation of electron orbitals. And now we have the first X-ray taken of a single atom, courtesy of scientists from Ohio University, Argonne National Laboratory, and the University of Illinois-Chicago, according to a new paper published in the journal Nature.

"Atoms can be routinely imaged with scanning probe microscopes, but without X-rays one cannot tell what they are made of," said co-author Saw-Wai Hla, a physicist at Ohio University and Argonne National Laboratory. "We can now detect exactly the type of a particular atom, one atom at a time, and can simultaneously measure its chemical state. Once we are able to do that, we can trace the materials down to [the] ultimate limit of just one atom. This will have a great impact on environmental and medical sciences." [...] Hla has been working for the last 12 years to develop an X-ray version of STM: synchrotron X-ray-scanning tunneling microscopy, or SX-STM, which would enable scientists to identify the type of atom and its chemical state. X-ray imaging methods like synchrotron radiation are widely used across myriad disciplines, including art and archaeology. But the smallest amount to date that can be X-rayed is an attogram, or roughly 10,000 atoms. That's because the X-ray emission of a single atom is just too weak to be detected -- until now.

SX-STM combines conventional synchrotron radiation with quantum tunneling. It replaces the conventional X-ray detector used in most synchrotron radiation experiments with a different kind of detector: a sharp metal tip placed extremely close to the sample, the better to collect electrons pushed into an excited state by the X-rays. With Hla et al.'s method, X-rays hit the sample and excite the core electrons, which then tunnel to the detector tip. The photoabsorption of the core electrons serves as a kind of elemental fingerprint for identifying the type of atoms in a material. The team tested their method at the XTIP beam line at Argonne's Advanced Photon Source, using an iron atom and a terbium atom (inserted into supramolecules, which served as hosts). And that's not all. "We have detected the chemical states of individual atoms as well," said Hla. "By comparing the chemical states of an iron atom and a terbium atom inside respective molecular hosts, we find that the terbium atom, a rare-earth metal, is rather isolated and does not change its chemical state, while the iron atom strongly interacts with its surrounding." Also, Hla's team has developed another technique called X-ray-excited resonance tunneling (X-ERT), which will allow them to detect the orientation of the orbital of a single molecule on a material surface.

Blurry

[saloomy]

These shouldnâ(TM)t count unless they are in focus. Much like that image of a black hole. You canâ(TM)t do real maths or analysis because the images are so blurry.

Re:

[DamnOregonian]

Fuck, I hope you're being ironic.

Re:

[Tarlus]

ironic

Nice.

Re:

[greytree]

Yes.

Just like you can't tell us your age, because it keeps changing.

Re:

[Anonymous Coward]

The maths says atoms are blurry too.

Re:

[LifesABeach]

spin.
it would be very interesting to see the axis directions that the various particles are spinning in.
given the size nucleus in relation to the type of atom being observed.
an application would be conversion of a neutron to a proton.
the excess energy released.
could be useful.
just throwing it out there

Isnâ(TM)t an X-ray too big

[fermion]

My understands NG is the wavelength of the photon has to be at least on the order of magnitude on the dimensions of the feature you want to resolve.

An X-ray can be have a wavelength as short as an angstrom but the inside of atom is much smaller than that.

Not really an X-Ray

[Roger W Moore]

It's not really an X-ray in the traditional sense that a photon provides the position information. It is really a reverse tunnelling electron microscope. The X-ray is used to excite a core electron of the atom so that it can tunnel across the potential barrier to the tip of a needle. As the needle where it generates an electronic signal. Hence, the position information comes from the needle, not the X-ray. By scanning the needle over the surface you get a picture of the atom because the tunnelling probability is exceptionally sensitive to changes in distance.

It seems to be really quite a clever method since it seems that they can extract information about the energy level of the electrons too.

Re:

[Luckyo]

The math involved must be headache-inducing. I remember my feeble attempts at quantum physics back in university, and the moment description mentioned using quantum tunneling excited electrons to the needle sensor, I started to get the same headache.

We sure have come a long way in quantum physics to be this precise while working with quantum uncertainty principle as the core tool.

Re:

[sonlas]

You made my day

Medical Diagnosis

[NoWayNoShapeNoForm]

Given the radiation exposure from that X-ray, that atom will likely develop some form of cancer in 5 to 10 years. /s

Re:

[Luckyo]

Technically, given the size of said atom, it would die of radiation damage instantly.

Remember, the order from least radiation harm to most is "cancer - cellular necrosis across entire body - liquefaction". And with this much intensity per this little mass, we're well in the liquefaction world.

So better hope is a dihydrogen monoxide atom.

Oh

[backslashdot]

I see the problem.Your electron's got a hairline fracture right here.
 

Re:

[Burdell]

Oh, and that'll be $10,000 - your insurance doesn't cover atomic X-rays.

What it says

[kmahan]

"If you can read this you're too close."