Scientists take first-ever X-ray photo of a single atom
A group of scientists from the Argonne National Laboratory at Ohio University and the University of Illinois at Chicago have for the first time in history been able to take an X-ray image of just one atom. This is a truly revolutionary achievement, as previously X-rays could be used to illuminate at least 10,000 atoms.
The results of the study were published in the journal Nature. The scientists also presented the resulting photo (scroll down to the end of the news to see the image).
Since the discovery of X-rays in the late 1800s, they have become an important tool in many fields. They have proven useful for imaging in medicine, materials science, archaeology, and astrophysics.
However, X-ray detection methods typically rely on the interaction of beams with many atoms, as the signal produced by a single atom is weak and difficult to distinguish from background noise.
Previously, the greatest achievement of scientists was the illumination of 10,000 atoms with X-rays. But the authors of the new study have jumped over their heads. Their discovery could potentially revolutionise the way scientists and researchers detect materials.
The study used iron and terbium atoms.
In order to photograph just one atom, the scientists had to modify the X-ray detectors with a sharp metal tip to which a synchrotron X-ray scanning tunneling microscopy (SX-STEM) system was connected. This system is used for nanoscale visualisation and characterisation of materials.
Simply put, SX-STEM allows scientists to understand the chemical composition of a material by viewing it with X-rays. To do this, the system excites (by providing energy) the electrons in the nucleus of an atom, which create a unique fingerprint. It is thanks to this imprint that scientists can determine the type of elements present in the material under study.
The study also used X-ray excited resonance tunnelling (X-ERT) to characterise the chemical states of atoms. This showed that X-ERT for the iron atom was dominant.
During the study, the scientists noticed that the X-ray signal could only be detected when the specialised tip was placed in close proximity to the atom. This confirmed that the detection was focussed on a single atom of interest to the researchers.
"This achievement ... opens up many interesting areas of research, including studies of the quantum and spin (magnetic) properties of just one atom using synchrotron X-rays," said lead author of the study, Professor Seo Wai Hla.
Earlier, OBOZREVATEL reported on the first-ever photo of DNA.