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Fig. 15.2. Feynman's letter to McLellan
expresses disappointment that McLellan
did not need to develop any new tech-
nology to build his motor but instead
had been able to use tweezers and a
microscope.
It was not until twenty-six years later, in 1985, that Feynman had to pay
out on the second prize. The scale of the challenge is equivalent to writing
the entire contents of Encyclopædia Britannica on the head of a pin ( Fig. 15.3 ).
The winner was Tom Newman, a Stanford graduate student who was using
electron beam lithography to engrave patterns on silicon to make inte-
grated circuits. A friend showed Newman a copy of Feynman's 1959 talk
and pointed out the section offering a prize for “writing small.” Newman
calculated he would have to reduce individual letters down to a scale only
fifty atoms wide. Using an electron beam machine, he thought it should be
possible. To check that the prize was still being offered after all that time,
Newman sent a telegram to Feynman. He was surprised to receive a tele-
phone call from Feynman confirming that it was. Because Newman was sup-
posed to be working on his thesis, he had to wait until his thesis adviser
went to Washington, D.C., for a few days before he made his attempt. He
programmed the machine to write the first page of Charles Dickens's novel
A Tale of Two Cities . The major difficulty turned out to be actually finding the
tiny page on the surface after it had been written. Newman duly received a
check from Feynman in November 1985.
Researcher Don Eigler ( B.15.1 ) and his colleagues at the IBM Almaden
Research Center in California used the scanning tunneling microscope (STM),
invented by their colleagues at IBM Zurich, to manipulate individual atoms and
create the world's smallest IBM logo in 1989 ( Fig. 15.4 ). They have also made
spectacular quantum “corrals” ( Fig. 15.5 ) and created “artificial” molecules, one
atom at a time ( Fig. 15.6 ), confirming another speculation of Feynman's:
Fig. 15.3. Stanford graduate student Tom
Newman wrote the first page of A Tale of
Two Cities by Charles Dickens using elec-
tron beam lithography to form letters
only fifty atoms wide.
It would be, in principle, possible (I think) for a physicist to synthesize any
chemical substance that the chemist writes down. Give the orders and the
physicist synthesizes it. How? Put the atoms down where the chemist says,
and so you make the substance. 4
In 2012, IBM researchers announced they had used the same technique to store
a single bit of information on a magnetic memory made of just twelve atoms.
According to researcher Sebastian Loth, it currently takes about a million atoms
to store a bit of information on a hard disk. Loth explains that:
B.15.1. Don Eigler achieved many
breakthroughs in nanotechnology
in his laboratory at IBM's Almaden
Research Center. His group produced
the smallest IBM logo using an STM
to position the individual atoms.
Roughly every two years hard drives become denser. The obvious question
to ask is how long can we keep going. And the fundamental physical limit is
the world of atoms. The approach that we used is to jump to the very end,
check if we can store information in one atom, and if not one atom, how
many do we need? We kept building larger structures until we emerged out
 
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