Extremely Fast Processes Recorded

Using pulses in the soft x-ray spectral region, scientists at the University of Kiel have demonstrated how quickly an intense laser can change the electrical properties of solids. The results of their research may lead to the development of optoelectronic components with faster data transmission rates or optical switches.

This laser system generated the ultrashort x-ray pulses that were used in the experiment to make the recordings. (Images: Rohwer et al, University of Kiel)

The new technique enabled the researchers to take snapshots of the electronic switching processes that occur within a fraction of a second. The images were then combined in a series to deliver a film depicting the switching process with a level of detail and temporal resolution never before achieved. The team was led by professor Michael Bauer, Dr. Kai Rossnagel and professor Lutz Kipp from the Institute of Experimental and Applied Physics at the University of Kiel, together with colleagues from the University of Kaiserslautern and the University of Colorado at Boulder, USA.

These two still frames were recorded using the newly developed imaging method. The time interval between them is only 0.00000000000007 seconds.

"These techniques that we have developed enable us to record films of extremely fast processes in a much more comprehensive manner than was previously possible with similar techniques. We are able to, for example, directly track phase transitions in solids or catalytic reactions on surfaces," Bauer said. "The amount of information gained from our pictures when played back in slow motion is vast. We will get completely new insights into most relevant electronic properties of solids which are important for a variety of current and future technologies, for example, in telecommunications."

The research was published in the March 9, 2011, edition of the journal Nature.

For more information, visit: www.uni-kiel.de