Scientists create a new technique to monitor chemical details of atoms

A new method of studying a fundamental property of electrons may have implications in atomic chemistry, quantum computing, and research related to dark matter.

With this technique, called "electron spin resonance," electrons play the role of tiny magnets. However, the electron must be in a single orbit around the atomic nucleus, while in materials, electrons are typically paired in orbits, canceling out their magnetic effect.

Introducing defects or impurities into the material can result in the appearance of individual electrons, similar to how free radicals are associated with cell aging or numerous chemical reactions.

Speaking to Agence France-Presse (AFP), Patrice Bertet, a physicist at the Atomic Energy and Alternative Energies Commission who contributed to the study published on Wednesday in the journal Nature, said, "We study these electrons using a technique dating back 70 or 80 years called electron spin resonance."

This technique, widely used in various fields such as chemistry, biology, material science, and food control, is rapid. However, it requires a large number of particles or atoms containing these unpaired electrons to detect any signal, making it impractical for microscopic samples.

The team at the Atomic Energy and Alternative Energies Commission's Quantronics Laboratory has developed a new method to monitor the rotation of a single electron, isolating "individual atoms and the rotation of a single electron, which was previously impossible," according to Bertet.

The principle of the new technique involves manipulating an atom containing a single electron by applying a small wave (microwave) pulse. When the electron returns to its ground state, it releases a small amount of energy in the form of a microwave photon, a small quantity of light. A commercial detection device is unable to detect such a weak signal, but the device developed by the commission's team can.

This new monitoring technique contributes to two research fields, namely chemistry and quantum computing.

In chemistry, it "may allow for much more precise characterization of the properties of matter around the atom," influencing molecular analysis and the study of the composition of molecules and the bonds between atoms.

Bertet points out that this technique is "initially applicable to all atoms or molecules containing unpaired electrons," in addition to the potential use for studying individual molecules or proteins.

The used atom in the experiment, erbium ion, possesses a distinctive property in quantum computing. Its magnetic momentum maintains its quantum properties for a significant period, around three parts per billion seconds. This is an extremely long period in quantum computing, allowing for the use of similar atoms as "qubits."

The physicist notes that the microwave photon detector has a "bright future" due to its rapid response to detecting "previously undetectable signals."

It can be used in experiments aimed at discovering dark matter, which is a theoretical component of matter in the universe. Similar research requires a photon detector that exhibits significant sensitivity to rapid effects.

 

AFP