Classic double-slit experiment in a new light

[Wrichik Basu]

An intense beam of high-energy X-ray photons (violet) hits two adjacent iridium atoms (green) in the crystal. This excites electrons in the atoms for a short time. The atoms emit X-ray photons which overlap behind the two iridium atoms (red) and can be analyzed as interference images.
Credit: Markus Grueninger, University of Cologne

An international research team led by physicists from Collaborative Research Centre 1238, 'Control and Dynamics of Quantum Materials' at the University of Cologne has implemented a new variant of the basic double-slit experiment using resonant inelastic X-ray scattering at the European Synchrotron ESRF in Grenoble. This new variant offers a deeper understanding of the electronic structure of solids. Writing in Science Advances, the research group have now presented their results under the title 'Resonant inelastic x-ray incarnation of Young's double-slit experiment'.

Related news.

Journal reference:

A. Revelli, et al. Resonant inelastic x-ray incarnation of Young’s double-slit experiment. Science Advances, 2019 DOI: 10.1126/sciadv.aav4020

Last Edit: Inserted correct picture.

 

[jedishrfu]

Please note that the Science Daily article shows the wrong picture thumbnail ie mentions ingestible robots. However, if you click on it you’ll see the diffraction image in the first post of this thread.

 

[Wrichik Basu]

Please note that the Science Daily article shows the wrong picture thumbnail ie mentions ingestible robots. However, if you click on it you’ll see the diffraction image in the first post of this thread.

They have corrected their mistake. Now, the proper picture can be seen.

 

[jedishrfu]

Not when I just clicked the link now. I even refreshed the page and it’s still there.

Perhaps they have another updated link or it’s a browser specific problem.

 

[Wrichik Basu]

Not when I just clicked the link now. I even refreshed the page and it’s still there.

Perhaps they have another updated link or it’s a browser specific problem.

Could be browser specific. When I edited the post the last time, I could view the correct picture. I can see it now as well. Maybe it has something to do with cookies.

 

[jedishrfu]

Ahh, it’s Girl Scout cookie time in the US that explains it. :-)

 

[sophiecentaur]

This excites electrons in the atoms for a short time.

I have a bit of a problem with that. If there are two different atoms absorbing then emitting, then how can the phases of the two 'slits' be consistent and how can a coherent interference pattern form? There must be something I am missing - what is it?

 

[mfb]

Only one of them absorbs it, but "we don't know which one" and the process is coherent.

 

[Wrichik Basu]

I have a bit of a problem with that. If there are two different atoms absorbing then emitting, then how can the phases of the two 'slits' be consistent and how can a coherent interference pattern form? There must be something I am missing - what is it?

From the main article:

The incident plane wave (blue) resonantly excites a core electron on one of two equivalent $Ir$ sites at $r_1$ and $r_2$. This intermediate state decays to a quasi-molecular final state, which is delocalized over both sites, i.e., without which-path information. The emitted x-rays interfere with each other, giving rise to a double-slit-type sinusoidal interference pattern as a function of the transferred momentum $q$, which points along $r_1 − r_2$.

Emphasis added.

This supports what @mfb has said above.

 

[sophiecentaur]

I was confused by the term "inelastic scattering" in the extract above when it seems that, in the paper (which I looked at later), they refer to "elastic" scattering. That would make a difference to whether there was phase coherence or not - I would have thought?