Electric charge displacement: where to?

A team of Italian scientists has developed a method that lays the foundations for investigating  electric charge transfer. The experiment, conducted at the Elettra Sincrotrone Trieste research centre, based in Area Science Park, has now landed on the pages of Nature.

The electric charge transfer from one atom to the other is a process on which the majority of chemical reactions and biological processes is grounded —such as cellular respiration, photosynthesis, or DNA oxidative damage. Understanding its fundamental laws is therefore crucial and the international scientific community has been seeking for decades an effective observation method. 

A decisive step in this direction was made by a group of Italian researchers at Elettra Sincrotrone Trieste, located in Area Science Park, which Nature’s latest issue reveals to have developed a method that creates an excitation and monitors its evolution, by means of light pulses produced by a free electron laser light source.

“Our research–explains Claudio Masciovecchio, head of the research team–is based on a process used by experimental physicists which is grounded on the interaction of light and matter. In this process a couple of light pulses with an appropriate wavelength are made to interact with some material and produce an excitation. This excitation can move through the material and its displacement can then be revealed by a third pulse”.

Elettra’s researchers have applied this method, using for the first time soft x-rays produced by a free electron laser source as pulses, thereby proving the effectiveness of this process in analysing the displacement of a vibration.

“The experiment’s success–adds Filippo Bencivenga, the research who conducted the investigation - proves that the method is effective even when light pulses having short wavelengths such as e x-rays are used, since they are the only ones suited to electrical dynamics. The next step will then be to extend the method to studying the displacement of the charge. This is a fundamental perspective from an application point of view as well, because grasping the mechanisms for energy transport and for electric charge transfer is the key not just to understanding a multitude of biological processes, but also for the targeted design of technologies in fields such as photovoltaic energy or medical diagnostics”.

In order to conduct this experiment the researchers used the FERMI free electron laser of the Elettra Sincrotrone Trieste research centre in Area Science Park. FERMI produces light flashes whose wavelength rages from ultraviolet and soft x-rays, both ultrabrilliant and ultrashort, whose power can reach one billion watts. Compared to other free electron lasers (four facilities operating worldwide), it has been designed in order to produce highly controllable and reproducible light pulses having exactly the required characteristics, thereby endowing researchers there with an exceptionally versatile instrument.  

Published paper: Nature doi:10.1038/nature14341
Four-wave mixing experiments with extreme ultraviolet transient gratings
F. Bencivenga, R. Cucini, F. Capotondi, A. Battistoni, R. Mincigrucci, E. Giangrisostomi, A. Gessini, M. Manfredda, I. P. Nikolov, E. Pedersoli, E. Principi, C. Svetina, P. Parisse, F. Casolari, M. B. Danailov, M. Kiskinova & C. Masciovecchio

Press Release 10.04.2015 (Laura Bibi Palatini, Elettra Press Office)


 


 


 

Last Updated on Tuesday, 14 April 2015 15:38