Headline, January10, 2014

''' THIS GREAT HUMAN - 

THIS GREAT SCIENTIST : 

DR HEINRICH ROHRER '''

BECAUSE he thought himself  no expert, he could bring to his work fresh, unbiased ideas, like those of the  students  whose company he so much enjoyed.

LIKE HIS STUDENTS, he did not think of obstacles, or feel the burden of fame.

In 1981, working at the IBM Research Laboratory near Zurich, he and his colleague Dr Gerd Binnig discovered that  ''quantum tunnelling''  could be done with a moving probe sharpened to a single atom at the tip.

They called it the Scanning Tunnelling Microscope (STM). When a voltage was applied to the tip, electrons leaked across the small vacuum gap that separated the tip from the surface it was hovering over.

This seemed impossible; but, under the laws of  quantum mechanics, a fundamental uncertainty in the energy of each electron meant that, for one instant, it was able to break through the barrier.

As the tip scanned back and forth, differences in the tunnelling current also showed up measurable variations in the atomic surface, revealing not only what atoms looked like but also what they might feel like if you could glide your fingers across the bumps.

''Topography''  was not quite the right word, since the STM was tracking electrical properties. But it gave each crystal surface a distinctive landscape, which to Dr Rohrer's joy often looked rather like the Alps.

With the right colour-coding of the STM trace of the surface of graphite, ''land''  rose out of blue lakes to become  green hills, merging to brown, and then to snow-capped peaks.

When in the late 1980s the STM was integrated with a computer  -the two technologies fortuitously appearing at the same time-   the 3D images became dazzling.

Carbon atoms clung together  ''very nicely''  in a honeycomb lattice. A crystal of gold made an arrangements of broad atomic terraces. A surface of silicon was revealed as a land of gentle. steadily rising undulations, in which the track of the probe could be seen like furrows dug with a plough.

Working at the nano scale,   one-billionth  of a metre, the STM did not merely touch atoms. It could also nudge them around, offering the prospect of building with them, as only  Nature  had done before.

The first attempt, by Don Eigler, in 1989, spelled out  ''IBM''  with 35 xenon atoms. Eager Utopians predicted that nanotechnology would one day lead to a  ''universal assembler'' , enabling scientists to build from the atomic level everything from cabbages to cars to human beings.

Dr Rohrer, ever down-to-earth, did not think that he and Dr Binnig had triggered a revolution. What pleased him the most about the STM project, apart from the results, was its simplicity and their own lighthearted approach to it:

Just tinkering with it on the side while doing other work for IBM. They had built the first STM on a shoestring budget, which satisfied his frugal mind: it was held together with a scotch tape, and operated  -to reduce vibrations-  only at night,  in breath-held silence.

No wild expectations. No big promises. But the gadget worked. Many other scientists had said it never could. They mocked the project, not least because Dr Rohrer and Dr Bennig had no background either in surface science or in microscopy.

Believers in the STM were hard to find at first. And this great scientist, --and both these great scientists, considered themselves with delight as neophyte in the field.

And then, and then, the pair received in 1986, the Nobel Prize for Physics. Thus they took their rightful place as chief pathfinders through the new nano-worlds.

His students miss him. Remember him as one original thinker with an A-rate mind. Dr Rohrer was a blessed man of the highest distinction. The world will never see the likes of him.

When asked if the Nobel Prize had changed him, he said simply : ''All in all, I think I did not lose the ground under my feet,''

With respectful dedication to all the Students, Professors and Teachers of Switzerland. See ya all on !WOW! -the World Students Society Computers-Internet-Wireless:

''' The Genius Issue '''

Good Night & God Bless!

SAM Daily Times - the Voice of the Voiceless