Quantum researchers introduce a controlled ‘wobble’ into the space of a single atom

Researchers from the Delft University of Technology in the Netherlands have been able to initiate controlled motion in the heart of atoms. They caused the atomic nucleus to interact with one of the electrons in the outermost part of the atom. This electron can be deflected and read through the needle of a scanning tunneling microscope.

The study, published in Natural communicationoffers the prospect of storing quantum information inside the nucleus, where it is unaffected by external disturbances.

For weeks on end, the researchers studied a titanium atom. “Atom Ti-47, to be precise,” says research leader Sander Otte. “It has one less neutron than conventional Ti-48, which makes the core less magnetic.”

This magnetism, “spin” in quantum language, can be seen as a kind of compass needle that can point in different directions. The direction of rotation at one time becomes the quantum information.

The nucleus of an atom floats in a relatively large space that is far from the orbiting electrons, and is unaware of its surroundings. But there is one exception: due to the very weak “hyperfine interaction”, the spin of one of the electrons can affect the nuclear explosion.

“It’s easier said than done,” says Lukas Veldman, who recently defended his Ph.D. thesis and research in honors. “Hyperfine synchrony is so weak that it only works in a small, well-tuned magnetic field.”

Once all the experimental conditions were met, the researchers used a voltage clamp to cause the electron beam to come out of the equation, after which the two colors collided for a fraction of a microsecond. “Exactly as Schrödinger predicted,” Veldman says.

Alongside those experiments, he made calculations that accurately reproduced the observed changes. The strong agreement between observation and prediction shows that no quantum information is lost during the interaction between the electron and the nucleus.

Good shielding from the environment makes nuclear weapons a suitable candidate for capturing quantum information. Current research may bring the device one step closer. But that is not what motivates the researchers.

Otte says, “This experiment gives people a sense of the state of things and small things that are unimaginable. To me, that makes it a worthwhile endeavor.”