The Tiny World of Quantum Control: Manipulating Atomic Nuclei
In a groundbreaking study conducted by researchers at Delft University of Technology in The Netherlands, a controlled movement was initiated in the very heart of an atom. The researchers were able to cause the atomic nucleus to interact with an electron in the outermost shells of the atom, manipulating and reading out the electron through the needle of a scanning tunneling microscope. Published in Nature Communications today, this research opens up possibilities for storing quantum information inside the nucleus, providing a safe haven from external disturbances.
For weeks on end, the team focused on studying a single titanium atom, specifically a Ti-47 atom. Lead researcher Sander Otte explains, “It has one neutron less than the naturally abundant Ti-48, giving the nucleus a slight magnetic property.” This magnetic quality, known as spin in quantum terms, acts like a compass needle pointing in different directions, representing valuable quantum information.
Precisely Tuned Experiments
The nucleus of an atom exists in isolation from the orbiting electrons, except for the rare influence of the hyperfine interaction that links the nuclear spin to an electron spin. Lukas Veldman, who recently defended his PhD dissertation, notes, “The hyperfine interaction is so weak that it requires a highly specific magnetic field to be effective.”
Voltage Pulse Manipulation
After meeting all experimental criteria, the researchers used a voltage pulse to disrupt the electron spin equilibrium, causing both spins to wobble in unison for a brief moment. Veldman adds, “This aligns with Schrödinger’s predictions, and our calculations mirrored the observed fluctuations remarkably well, reaffirming that no quantum information is lost during the electron-nucleus interaction.”
Unlocking Quantum Potential
The ability to shield the nuclear spin from external influences positions it as a promising medium for storing quantum information. While this research pushes towards realizing practical applications, the team is motivated by the profound impact of exerting control on matter at the smallest conceivable scale. Otte concludes, “This experiment empowers humans to manipulate matter on a minuscule level, making it a pursuit worthwhile in itself.”