A strong laser beam can remove an electron from an atom -- a process which takes place almost instantly. At the Vienna University of Technology, this phenomenon could now be studied with a time resolution of less than ten attoseconds (ten billionths of a billionth of a second). Scientists succeeded in watching an atom being ionized and a free electron being "born." These measurements yield valuable information about the electrons in the atom, which up until now hasn't been experimentally accessible, such as the time evolution of the electron's quantum phase -- the beat to which the quantum waves oscillate.
The time span of ten attoseconds (10*10^(-18) seconds) is so short that any comparison to everyday timescales fails. The ratio of ten years to a second is 300 million to one. Dividing a second by the same factor takes us to the incredibly short time scale of three nanoseconds -- in this period, light travels one meter. This is the time scale of microelectronics. Again dividing this tiny period of time by a factor of 300 million, we arrive at about ten attoseconds. This, is the timescale of atomic processes. It is the order of magnitude of an electron's period orbiting the nucleus. In order to measure or to influence these processes, scientists have been striving to access these timescales for years.
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