Scientists create first molecular Bose-Einstein condensate in historic physics breakthrough

In a progressive achievement in Quantum physics, the research team at Columbia University has successfully produced a Bose-Einstein condensate (BEC) from molecules, reaching a dream scientists have chased for decades.

Physicist Sebastian Will and his team have successfully cooled sodium-cesium molecules to an unprecedented 5 nanoKelvin (approximately minus 459.66 degrees Fahrenheit). As detailed in the journal Nature, this extreme cooling caused the molecules to cease their individual behavior and collapse into a single quantum state.

Creating this molecular Bose-Einstein Condensate (BEC) has been a significant challenge. While atomic BECs were first achieved in 1995 (a feat that earned a Nobel Prize), molecules present a greater difficulty. Their complex rotation and vibration, coupled with their tendency to destroy one another upon collision, have historically made sufficient cooling almost impossible. The team’s work overcomes this “collision” problem.

The breakthrough came via a collaboration with Tijs Karman from Radboud University in the Netherlands. The team utilized a process called “microwave shielding.” By applying two specific microwave fields, they created an energy barrier that caused the molecules to repel each other rather than collide.

This protection permitted the sample to survive “evaporative cooling,” where the hottest molecules are removed to lower the overall temperature.

The resulting condensate lasted for approximately two seconds. This is an unusually long lifespan for such a fragile system.

“Molecular Bose-Einstein condensates open up whole new areas of research, from understanding truly fundamental physics to advancing powerful quantum simulations,” said Will. “This is an exciting achievement, but it’s really just the beginning.”

The initial phase of the experiment involved approximately 30,000 molecules, which ultimately yielded a pure condensate of about 200 molecules.

What makes these molecules, specifically sodium-cesium, so valuable is their unique characteristic: unlike atoms, which primarily engage in short-range interactions, these polar molecules possess uneven electric charges that facilitate long-range interactions. This attribute makes them exceptionally suitable for simulating complex materials and probing exotic quantum phases of matter.

Jun Ye, a prominent figure at JILA, praised the effort as a “marvelous achievement in quantum control technology.” The Columbia team’s next step is to utilize lasers to configure these molecules into artificial crystals, a technique that could potentially unlock new, fundamental insights into the workings of the universe.