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IF YOU want to watch a chemical reaction close up, you need a camera fast
enough to snap electrons as they make and break bonds. But electrons are speedy:
their movements are measured in attoseconds, and a billion billion attoseconds
go by every second. Ferenc Krausz at the Technical University of Vienna and his
team are the first to generate attosecond laser pulses that you could use to
watch electrons (Nature, vol 414, p 511). They shone a short pulse of
red laser light onto a jet of neon atoms. The laser鈥檚 oscillating electric field
pulled electrons out of the atoms and crashed them back in, sending out X-ray
pulses just 650 attoseconds long.