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A glimpse into Attosecond Physics
- Atoms’ natural time scale is incredibly short.
- In a molecule, atoms can move and turn in millionths of a billionth of a second, known as femtoseconds (10 −15 seconds).
- But when electrons move inside atoms or molecules, they do it so quickly that changes are blurred out even in a femtosecond.
- In the world of electrons, positions and energies change at speeds of between one and a few hundred attoseconds.
- An attosecond is one billionth of a billionth of a second.
- An attosecond is so short that that the number of them in one second is the same as the number of seconds that have elapsed since the universe came into existence, 13.8 billion years ago
- On a more relatable scale, we can imagine a flash of light being sent from one end of a room to the opposite wall – this takes ten billion attoseconds.
- So far, it was possible to observe atomic processes during the durational period of a femtosecond, nothing beyond that.
- This year’s laureates conducted experiments that opened up the new research field of attosecond physics.
- The trio of scientists, in different countries, did the experiments that demonstrated that attosecond pulses could be observed and measured.
How did they do this?
- L’Huillier discovered that when a laser light wave was passed through a noble gas, it interacted with the atoms, giving some electrons extra energy that was then emitted as light.
- Pierre Agostini succeeded in producing and investigating a series of consecutive light pulses [or flashes of light], in which each pulse lasted just 250 attoseconds.
- Ferenc Krausz was working with another type of experiment, one that made it possible to isolate a single light pulse that lasted 650 attoseconds.
- These flashes of light made it possible to provide images of processes inside atoms.
Why is this work important?
- Attosecond physics gives us the opportunity to understand mechanisms that are governed by electrons. The next step will be utilising them.
- One possible application is to study molecular-level changes in blood, to identify diseases.
- A better understanding of how electrons move and transmit energy can also help in creating more efficient electronic gadgets.