Internal atomic event captured before you can say “zeptosecond”
Scientists have measured the interval between a photon striking an electron in a helium atom and it being ejected with an accuracy of a trillionth billionths of a a second
More…
CrazyNeutrino said:
Internal atomic event captured before you can say “zeptosecond”Scientists have measured the interval between a photon striking an electron in a helium atom and it being ejected with an accuracy of a trillionth billionths of a a second
More…
More …
This phenomenon, known as photoionization, whereby an ion is formed through the interaction of a photon with an atom, is specifically related to the quantum-mechanical redistribution or absorption of energy within an atom – namely, the photon’s energy is either distributed between the two electrons in the helium atom, or completely absorbed by one of them. Whichever way things go, one of the electrons is ejected from the atom and being able to measure the time interval between photon strike and electron release is therefore very important in verifying an aspect of quantum theory.
It had not occurred to me that quantum mechanics could be validated in such a way, a way that is both incredibly simple and unbelievably difficult to measure.
mollwollfumble said:
CrazyNeutrino said:
Internal atomic event captured before you can say “zeptosecond”Scientists have measured the interval between a photon striking an electron in a helium atom and it being ejected with an accuracy of a trillionth billionths of a a second
More…
More …
This phenomenon, known as photoionization, whereby an ion is formed through the interaction of a photon with an atom, is specifically related to the quantum-mechanical redistribution or absorption of energy within an atom – namely, the photon’s energy is either distributed between the two electrons in the helium atom, or completely absorbed by one of them. Whichever way things go, one of the electrons is ejected from the atom and being able to measure the time interval between photon strike and electron release is therefore very important in verifying an aspect of quantum theory.It had not occurred to me that quantum mechanics could be validated in such a way, a way that is both incredibly simple and unbelievably difficult to measure.
More …
To achieve such blistering capture speeds, the researchers fired an attosecond-long, extremely ultraviolet (XUV) light pulse onto a helium atom whilst simultaneously shooting a four femtosecond infrared laser pulse at the same area. When the electron was ejected, it was immediately detected by the infrared laser pulse. Depending on the state of the oscillating electromagnetic field of the laser pulse at the time of capture, the released electron was either accelerated or decelerated by the photon interaction and measurements of this speed change enabled researchers to record the length of the photoemission event down to zeptosecond accuracy.
Incredible. For starters, synchronising the IR and UV lasers to attosecond accuracy, how the heck did they arrange that. And that’s only the first of the technical challenges.
I thought “Jack Robinson” was the official time unit before “they” invented milli and micro seconds.