Scientists have achieved a groundbreaking feat by creating the coldest large molecule ever observed, featuring a peculiar chemical bond. This remarkable achievement was unveiled in a recent study published in the journal Nature, where researchers detailed the production of a never-before-seen four-atom molecule under extreme cold conditions.


The molecule, a unique configuration of sodium-potassium with an extraordinarily elongated chemical bond, was synthesized at a chilling temperature of 134 nanokelvin, merely 134 billionths of a degree above absolute zero. This achievement is significant because ultracold systems offer a platform to explore quantum behavior, which is dominated by quantum mechanics at such low temperatures. Understanding quantum behavior in molecules holds promise for various applications, including the development of high-temperature superconductors and advanced materials for lithium batteries.


However, creating ultracold molecules presents significant challenges due to their complex quantum states, which are orders of magnitude more numerous than those of atoms or ions. To overcome this hurdle, the research team led by Tao Shi employed a sophisticated cooling technique involving laser cooling followed by evaporative cooling. Laser cooling, a method commonly used for atoms, involves bombarding the moving atom with laser beams from multiple directions, causing it to absorb and then release energy, thereby cooling itself. While adapting this technique for molecules is daunting due to their numerous quantum states, the researchers ingeniously utilized ultracold atoms, specifically sodium (Na) and potassium (K), as a precursor to form diatomic NaK molecules.


However, the process of associating cold atoms into molecules introduces heating, necessitating further cooling through evaporative cooling. Despite the technical challenges associated with this approach, the researchers successfully manipulated microwaves to control the association of NaK molecules, overcoming clumping issues and facilitating the formation of a unique four-atom molecule, (NaK)2. Remarkably, this molecule possesses a central bond a thousand times longer than the bond between its constituent atoms and was created at a temperature over three thousand times colder than any previously recorded four-atom molecule.


This groundbreaking achievement opens new avenues for exploring quantum phenomena in complex molecular systems, offering insights into fundamental physics and potential applications in diverse fields such as materials science and energy storage. As Roman Bause, a quantum optics researcher involved in the study, remarked, these findings hold promise for delving into uncharted territories where theoretical understanding is currently lacking, paving the way for transformative advancements in technology and scientific knowledge.

свернуть