A New Form of Matter

One of the most extraordinary aspects of Bose-Einstein condensates is that they are quantum creatures big enough to see. And there lies much of their promise. Many of today's cutting-edge technologies - smaller, faster computer chips, micro-electro-mechanical systems (MEMS) and quantum computers - lie in the twilight zone between the quantum world and the macroscopic world. Scientists hope that studying BEC's will advance those technologies and create others.

more Atom-laser pulses produced in Ketterle's lab. The curved shape of the pulses was caused by gravity and forces between the atoms.

Ketterle is already experimenting with one: a pulsed atom-laser.

"In an ordinary gas, atoms move around randomly, they flit around in all directions. But in a BEC, all the atoms march lock-step," Ketterle explains. "They are just one single matter-wave propagating in one direction."

Atom-lasers are akin to light-lasers, which are beams of photons that likewise "march lock-step." But there are differences: For instance, atom-laser beams have mass so they will bend downward in Earth's gravitational field. Light-laser beams are massless; they bend, too, but the effect is very small. Furthermore, light-lasers pass through air with ease. Atom-laser beams will be substantially scattered by air molecules.

"Atom lasers need a vacuum to retain their properties," notes Ketterle. As a result they won't be used in the same way as light-lasers. They won't improve CD players or supermarket scanners, for instance. But atom-lasers will doubtless find uses of their own - "like better atomic clocks [which will improve spacecraft navigation - a boon to NASA], atomic optics or very fine lithography," says Ketterle.

Who knows where BEC's will lead? After all, humans evolved on this planet with solids, liquids and gases all around, and we're still figuring out innovative uses for them. With Bose-Einstein condensates ... we're just getting started.