This was significant because ordinarily the nuclear spin, a process that describes the magnetism of the atom’s core, can only be detected in very large numbers. Hyperfine refers to the coupling between a single atom’s nuclear spin and its electron counterpart, causing small shifts and splittings in the energy levels of atoms, molecules, and ions.
This was achieved through the use of a Scanning Tunneling Microscope, which is an instrument for imaging surfaces at the atomic level. The microscope is based on the concept of quantum tunneling, where a particle passes through a potential barrier that it classically cannot surmount.
With the microscope function, when a conducting tip is brought very near to the surface to be examined, a bias (voltage difference) applied between the two can allow electrons to tunnel through the vacuum between them. The resulting tunneling current is a function of tip position, applied voltage, and the local density of states. This can be visualized in image form.
In terms of the research implications, the science team aims to use this sensitivity of the hyperfine interaction within the chemical environment as a quantum sensor.
Speaking with Phys.org about the research, lead scientist Professor Andreas Heinrich said: “I am very excited about these results. It is certainly a milestone in our field and has very promising implications for future research. By addressing individual nuclear spins we can gain deeper knowledge about the structure of matter and open new fields of basic research.”
The research has been published in the journal Science. The associated paper is titled “Hyperfine interaction of individual atoms on a surface.”