In a Columbia University laboratory, sodium and cesium molecules at temperatures of billionths of a degree above absolute zero suddenly stopped vanishing within fractions of a second. Scientists led by Sebastian Will managed to extend their lifetime more than a thousandfold — to a full second and longer. This is not merely a technical record but a fundamental shift in quantum physics.
Ordinary ultracold molecules collide and react quickly, turning into other substances. To avoid this, the researchers applied a microwave "blanket": two microwave fields create a protective layer around each molecule that repels them from one another at close range. As a result, the sample remains stable, and the temperature drops to 36 nanokelvins — just a few nanokelvins above the point where the molecules should form a Bose-Einstein condensate.
Such stability opens access to regimes where quantum effects manifest especially vividly. Molecules possess a strong dipole moment, so their interactions act over long distances and can be precisely tuned. This makes it possible to model complex quantum materials that cannot be created by other means — from superconductors to new phases of matter.
In everyday life this sounds abstract, but it is precisely such platforms that underlie future quantum simulators and sensors. They will help us understand how collective quantum states arise in real substances and may lead to new materials with unusual properties — from room-temperature superconductors to a new generation of quantum computers.
Now that the molecules live long enough, experimenters can observe their self-organization into droplets and even crystal-like structures. The next step is to fully form a molecular condensate and study its properties in a strongly interacting regime. Each new measurement brings us closer to understanding the quantum world, where the usual rules cease to apply.
