Scientists recently made a significant achievement by identifying an element using X-ray imaging on a single atom. The discovery marks a major milestone in the sciences, especially considering that previous attempts could only detect an attogram — equivalent to roughly 10,000 atoms. This development has far-reaching implications in various scientific fields, such as medicine and security, given that X-rays have been a vital tool since their discovery by Wilhelm Conrad Rontgen in 1895.
New Technique for Single-Atom X-Raying
Scientists utilized a technique known as synchrotron X-ray scanning tunneling microscopy (SX-STM) to capture the X-ray signature of a single atom. SX-STM is a combination of synchrotron X-rays, high-energy X-rays produced by electrons accelerating in a circular track, and scanning tunneling microscopy, which uses a sharp metal pointer interacting with a sample’s electrons at close distances. The high-energy X-rays stimulate the sample, while the metal pointer collects photoelectrons emitted by the atom, thus revealing its chemical state and identity.
The Importance for Material Science
This new methodology carries significant weight in materials science — a study area focusing on solid materials’ properties and how their composition and structure determine these properties. It provides insights into the atomic-scale properties and interactions of materials, enabling scientists to understand molecular structures and behaviors precisely. The method also facilitates the design and creation of novel materials and devices, and enhances knowledge of biomolecular interactions, catalytic activity, and quantum phenomena.
Understanding X-Rays
X-rays are electromagnetic radiation forms with higher energy, frequency, and shorter wavelength than visible light. They can penetrate through most objects, such as bodies, producing images of internal structures. X-rays are produced either by decelerating or accelerating charged particles or by exciting atoms. They’re used widely in science, medicine, industry, and security applications for various tasks, such as diagnosing diseases, detecting bone fractures, identifying materials, and scanning luggage.
Visible Light Communication (VLC) Technology
Visible Light Communication (VLC) employs visible light for communication that occupy the electromagnetic spectrum from 375 nm to 780 nm. Known as short-range optical wireless communication, VLC, a kind of Li-Fi, has a range of approximately 10 meters and it cannot pass through walls or any solid object. It can transmit large amounts of data faster than Bluetooth, providing high speed internet up to 10 Gb/s. VLC has no electromagnetic interference, making it a better solution in areas sensitive to electromagnetic radiation such as aircrafts.
Radio Waves and Electromagnetic Fields
Radio waves, part of the electromagnetic (EM) spectrum, are energy forms that travel and spread out. Along with visible light, they share the EM spectrum with microwaves, infrared light, ultraviolet light, X-rays and gamma-rays. This spectrum was unified under a theory by Scottish physicist James Clerk Maxwell in 1873. He proved that magnetic poles come in pairs that attract and repel each other, much like electric charges. Magnetic electric fields of an electromagnetic wave are perpendicular to each other and to the wave’s direction. Radio waves, at the lowest range of the EM spectrum, bend in both the magnetic and electric fields due to their electromagnetic nature.
