For the first time in the history of the world, the multiplication of light within a molecule has been measured within a process that falls in zeptoseconds. The research has been covered by physicists from Goethe University Frankfurt along with teammates from the DESY and Fritz-Haber-Institute.
Ahmed Zewail got the noble prize for calculating the speed at which the shape of the molecule changes in 1999. He is the founder of Femtochemistry with an ultrashort laser the arrangement and breaking up of chemical bonds that occurs in femtoseconds which is equal to 0.000000000000001 seconds (10-15 seconds).
Now, after such a long time physicists Reinhard Dörner’s team from Goethe University researched a process that is shorter than femtoseconds. Measurement was done to know How long does a photon takes to cross a hydrogen molecule?
It is 247 zeptoseconds(zs) (1 zeptosecond = 0.000000000000000000001 seconds, or 10−21 second) for the average bond length of the molecule. This is the shortest timespan ever recorded in the whole world until now.
Image Source – aktuelles
The calculation of the time was carried on a hydrogen molecule (H2) that was irradiated with X-rays from synchrotron light source PETRA III at Hamburg accelerator centre DESY. The energy of the x-ray was set so that one photon can discharge both electrons out of the hydrogen molecule.
The interference pattern of the first discharged electron was measured with the help of the COLTRIMS reaction microscope. Its advancement was done by Dörner which helps to see the ultrafast reaction processes in atoms and molecules. The COLTRIMS reactions microscope also grants the decision of the orientation of the hydrogen molecule. The second electron also left the hydrogen molecule which became an advantage for the researchers and the rest of the hydrogen nuclei flew apart and was cached.
Sven Grundmann said, “Since we knew the spatial orientation of the hydrogen molecule, we used the interference of the two-electron waves to precisely calculate when the photon reached the first and when it reached the second hydrogen atom.”
He also added, “And this is up to 247 zeptoseconds, depending on how far apart in the molecule the two atoms were from the perspective of light.”
“We observed for the first time that the electron shell in a molecule does not react to light everywhere at the same time. The time delay occurs because information within the molecule only spreads at the speed of light. With this finding we have extended our COLTRIMS technology to another application,” said Reinhard Dörner.
Source – aktuelles