Austrian scientists have measured the shortest time interval ever, according to Nature in "Snapshot taken of the tiniest time interval."
A group led by Ferenc Krausz of Vienna University of Technology used pulses of laser light to watch electrons moving around atoms, and were able to distinguish events that took place 100 attoseconds -- or 10-16 seconds -- apart.
These scientists seem unstoppable. They only broke the femtosecond barrier last June. For more details and illustrations, check this former story.
Krausz and his team say that the research could improve understanding of the role of electrons in superconductivity and in giant magnetoresistance, a magnetic effect used in data-storage devices. "It's only on the attosecond timescale that you see these things happening," says Roger Falcone, a physicist at the University of California, Berkeley.
How did the team achieve this result?
Krausz used ultraviolet-light pulses of 250-attosecond duration to excite electrons in atoms of neon, raising them to a higher energy level. These electrons come out of the atoms with a range of different momenta. A second pulse of light, delivered just after the first, then gives the electrons an extra jolt. Changing the delay between these two pulses produces a different distribution of momentum values for the electrons, which the scientists measured with a sensitive electron detector called a 'streak camera'. Comparing these distributions gave the team a snapshot of how the electrons differed when hit with an early or late second pulse.
Source: Mark Peplow, Nature, February 26, 2004
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