Atom-moving experience at IBM laboratory

Net Results: This week I am thrilled to be one of a small number of people in the world who can say that, although I may not have moved mountains in my lifetime, I certainly have moved atoms.

Yes, I know, you'll say that you've moved atoms every time you've picked up a coffee mug - every time you move, full stop. But the difference is that you moved trillions of atoms all at the same time, which any old person can do. Just try picking them up one or two at a time, and then setting them down just where you want them to be. A bit harder, eh?

To do that, you need special equipment - as it turns out, about half a million dollars worth of homemade microscope, if you are IBM and happen to have the specialised parts sitting around your 690-acre research laboratory in the hills of Northern California. The "specialised parts" turn out to rather endearingly include lots of aluminium foil for wrapping around bits here and there and some kitchen sponges clamped on for good measure.

At IBM's beautiful Almaden Lab on a hilltop near San Jose, two such microscopes - called scanning tunnelling microscopes - sit in their own rooms where they are at the centre of several nanotechnology projects headed up by youthful researcher Andreas Heinrich.

Correction: call that nanoscience.

"I'm always wary of calling this 'technology'," he says of the experiments his lab is doing in moving atoms and building infinitesimally small structures with them. "I'm not happy that the word 'nanotechnology' gets used all the time because it implies a product. Nanoscience is a better word. If we're lucky, we might get the science to make a technology."

Most of what his lab does is "proof of concept", he says. For example, his group has succeeded in creating a string of atoms in a zig-zag shape that can be made to snap into alignment in one direction like tumbling dominoes. This creates a two-state system - using the domino analogy, the atoms are either up or down.

As computing fans will know, once you have anything that can be in two states, you have the basics for creating a computer system, as data is stored and processed by means of recording it as a series of ones and naughts. The ones and naughts can be represented by any on-off, up-down, charged-uncharged means, as long as there are two states.

What Heinrich's group has indicated is that, theoretically, they have found a way of building a nanocomputer - a computer so small it cannot be seen, capable of storing and handling endless amounts of data, operating on the curious level of quantum physics, where our real world large-scale view of reality is turned upside down.

Heinrich says that he personally doesn't believe this particular method will result in a dinky PC, but the proof of concept is "a demonstration that these things are possible". Maybe 50 years from now, he says, there will be practical applications.

That is the kind of luxurious timescale allowed in a pure research lab that, as Heinrich notes, can do the kind of work even the best academic labs cannot do due to lack of money, equipment and shorter perspectives.

The scanning tunnelling microsocope is an extraordinary thing, as one would imagine of a tool that allows you to pluck up a single atom and set it down a few atom-lengths away. It has a teensy tip made of a single iridium wire spun out as thin as can be. It is held in position by a housing so stable that it only moves 10-1,000ths of a nanometer - or 1,000th of an atom - and can attach to a single atom on demand.

A tiny substrate of copper atoms form the surface on which other atoms or basic molecules are scattered for manipulation. The sample is held in liquid helium - at -270 degrees - to make the atoms as stable as possible. The electrons in the tip of the microscope interact with the electrons in the sample atoms, forming a bond that enables the tip to lift the atoms.

So how do you move atoms? Using two refrigerator-sized banks of computing equipment and an old IBM Pentium PC, keyboard and mouse, attached to the microscope, that's how. You drag and drop. I kid you not.

"Who wants to move some atoms?" asks Heinrich, and his six visitors jump at the chance. Sensitive equipment offers a computer screen representation of what is right under the microscope's tip - 11 carbon monoxide molecules (simple two-atom molecules), which look like one-inch golfballs half submerged in a bumpy green.

To move one, I first click the left mouse button to activate the tip. Then I click on the molecule I want to move, scroll to where I want to drop it, and click again. Surprisingly, a noise like the sound of a chair being dragged across a tile floor starts up.

"That's the sound of the atoms being pulled across the substrate of copper atoms," says Heinrich.

They get unstable when they are pulled over another atom and the computer picks up that vibration as noise.

The computer screen performs a rescan and there is my molecule on the other side of the screen. It is so mind-boggling, so extraordinary and requires such a willing suspension of disbelief that I am waiting for the Third Policeman to burst through the door in search of Omnium.

That doesn't happen but I think what does would have pleased Flann O'Brien. Tasked with moving atoms around on screen, six journalists decided to make a smiley face out of them.

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