Absolute zero near, ion and atomic mixtures are “present” for the first time

Researchers have been conducting laser cooling experiments on atoms and ions for decades, but no one has observed a mixture at very low temperatures. Dutch scientists have placed niobium ions in a lithium-ion cloud that cools up to absolute zero, and for the first time have observed a mixture of atoms and ions at very low temperatures, promising to promote the development of quantum technology, the Physicist Sina.com reported Tuesday.


In the latest study, Dr. Rene Gretesma of the University of Amsterdam and his colleagues first used laser cooling technology to cool individual niobium ions, and they also prepared a separate atomic gas mass of about 10,000 lithium atoms and cooled them to near absolute zero. They then used a set of tools to overlap ions with atomic clouds and monitor the ion energy level, ultimately determining the energy generated by the collision between ions and atomic clouds.

“Cold atoms and ions are expected to help us better understand quantum polymer phenomena, which can also be used in atomic clocks and even in quantum computers, but so far no one has created a mixture of atoms and ions at such extremely cold temperatures, and we were the first to achieve this,” Gretesma said. “

“The main challenge of our experiment was to keep ions confined to the gas, and for that, we applied electric fields,” she explains. But previous studies have shown that electric fields have a negative effect on atomic-ion collisions, causing them to heat up, and we reduce the thermal effects by using heavy ions and light atomic lithium. “

The observations, published in the latest issue of the journal Nature Physics, reveal some of the effects that could affect the development of new quantum technologies.

“For the first time, we have observed that ions in neutral atomic gases are cooled to a state where quantum effects become important, and that the system can be used to study quantum chemistry on a single particle scale, or to find a way to work in quantum multibody physics of interacting atoms and ions, or even in the field of quantum computers,” Gretesma said. “

The team also found evidence of quantum phenomena that point to collisions between ions and atoms, and the new findings could have implications for future research.