The first practical atom laser is a step closer today thanks to Australian researchers.

The researchers have shown how to refuel the laser with ‘quantum foam’ allowing continuous operation. The results, reported 12 July in Nature Physics, hold great promise for precision measurement in navigation, industry and mining and for fundamental tests of quantum mechanics.

Ten years ago the first atom laser brought its US inventers a Nobel prize. They discovered how to persuade ‘quantum foam’ (more properly known as Bose-Einstein condensate) to produce a beam of matter waves just as lasers produce an intense light beam.

Scientists hope to use this ‘atom laser’ as the basis for a swathe of new devices, some offering staggering improvements in measurement sensitivity.

However, until now there has been a problem: the atom laser quickly drained the source material, and the device switched off. Such short-term operation is fine for fundamental research, but for applications it’s a dead end.

“We discovered how to refuel the material, potentially allowing continuous operation of the atom laser,” says lead author, Nick Robins from the Australian National University.

“We had to overcome a series of theoretical and technical hurdles, mainly related to the delicate nature of the Bose-Einstein condensate. It only exists at near absolute zero and is hard to maintain.”

“Our work paves the way for a potentially unlimited source of ultra-high brightness atoms. It’s like going from a trickle of atoms leaking from a thimble to turning on an atom tap,” says Nick.

The atom laser offers the possibility of measurement of magnetic fields, electric fields, gravitational fields, rotations and accelerations with a sensitivity undreamt of a few years ago. Applications can be expected in medical research, mineral exploration, and navigation both on earth and in space.

“We all march to the beat of precision measurement. Modern atomic clocks, for example, lose or gain about one second in one hundred-million years and are at the heart of GPS navigation,” says Nick.

“Our ability to precisely measure length has allowed us to produce ever smaller and faster electronics that form the basis of our mobile phones, our computers and the internet. Precision measurement is at the heart of our technology driven society.”

John Close, an ANU co-author on the paper says “Our job right now is to compare devices made with an atom laser to the current cutting edge of measurement technology and really answer the question: how much better are these devices? That’s the next big step, and the one that industry and government are waiting for.”

An ‘atom laser’ is essentially an ultra-bright beam of atoms.  Normally atoms behave like microscopic billiard balls, bouncing around, independently of one another.  However, in an atom laser they are made to behave like waves, flowing and moving together in a highly organised, or coherent, way.  The difference between an atom laser and normal atoms is analogous to the difference between an optical laser and a light bulb.

Nick Robins is one of 16 early-career scientists chosen for Fresh Science 2008, a national program sponsored by the Federal and Victorian governments.