FCUP develops the world's fastest ultrafast laser system

A team of scientists from the Faculty of Sciences of the University of Porto (FCUP) has developed and built a new ultra-fast laser system for producing and observing magnetic processes on an unprecedented time scale of less than 10 femtoseconds (1 femtosecond = 0.000,000,000,000,001 seconds), setting a new worldwide limit for the speed at which the magnetization of materials can be modified directly with laser light. The new system and the results obtained are expected to have an impact on the development of new magneto-optical materials and technologies, for applications in biomedical sensors and for recording and reading information at high speed, and have earned a publication in the prestigious journal Scientific Reports, an open-access publication from the Nature group.

Helder Crespo, a professor at the University of Porto, and David Schmool, a former professor at the University of Porto, currently director of research at the CNRS (Centre National de la Recherche Scientifique, France) and professor at the University of Versailles, led the team of scientists at the University of Porto. FCUP Physics and Astronomy Department (Group of Ultrafast Lasers and Magnetodynamic Spectroscopies of IFIMUP-IN - Institute of Materials Physics of the University of Porto), which reached these results through strategic scientific planning, which included three projects supported by FCT.

In Helder Crespo's opinion, "the support of the FCT was crucial for the development of all scientific activity, from the acquisition of components and instruments for the construction of the various systems, to the advanced training of human resources", and five doctoral theses were developed within the scope of these projects.

These advances are directly related to a new technology for compressing and measuring ultrashort laser pulses, called dispersion-scan (or d-scan), invented and patented at the University of Porto in collaboration with Lund University. This revolutionary technique is also the basis of a new high-tech company based in Porto, Sphere Ultrafast Photonics (a spin-off from the University of Porto), which manufactures and distributes this exclusive technology on the world scientific market.

Today it is possible to store large amounts of information on digital magnetic media, which has to be accompanied by a corresponding increase in writing and reading speed. Otherwise, the system in question becomes slow compared to its capacity. Studying and understanding the fundamental phenomena behind magnetism is a very important challenge in this cutting-edge technology, where we are trying to find out the maximum speed at which we can read and write bits on magnetic material, and how we can do it.