Scientists measure very short laser pulses

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LONDON, England (UPI) -- British scientists have created a technique for accurately measuring and controlling electromagnetic waves within extremely short laser pulses.

The Imperial College London researchers say being able to fully understand and control such laser pulses represents an important step toward using them to track and manipulate electrons in leading-edge research at the subatomic level.

The study focused on laser pulses less than 10 femtoseconds long -- a femtosecond is 1 million-billionth of a second. Such pulses can allow scientists to move and control electrons in atoms and molecules, and to understand, for example, how molecules are formed.

The physicists attained an unprecedented level of accurate measurement by firing the femtosecond laser pulse into a sample of gas, which responds by emitting an X-ray pulse that`s up to 10 times shorter than the original laser pulse.

The researchers found the spectrum of the X-ray pulse encoded all the information necessary to precisely reconstruct the waveform of the original laser pulse. Through careful measurements and some 'intelligent' software designed specifically for the purpose, the researchers were able, for the first time, to measure the waveform of individual femtosecond pulses.

The study is detailed in the journal Nature Physics.

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