The European XFEL will create unique conditions for the investigation of atoms, molecules, atomic clusters or nanoparticles in extremely high X-ray radiation fields. These insights can lead not only to progress in basic research, but also to new products – such as novel catalysts or electronic devices controlled by X-ray radiation.
The X-ray flashes of the European XFEL will enable novel experiments with atoms, molecules, ions or clusters. Thanks to the high intensity of the flashes, the particles are excited into new, previously unknown states. The European XFEL thus creates a unique environment for basic research, which will allow completely new insights into processes that could not be explored so far.
Highly ionized states
One example are highly ionized states in which the particles lose several electrons at once. In these ionized states the particles exhibit new properties. Investigating these states – which scientists were unable to observe so far – is very important for our understanding of atomic physics phenomena. Such insights could also benefit research into energy generation.
The European XFEL will also provide new insights into the world of atomic clusters – loosely bound arrangements of atoms ranging from a few atoms to up to several ten thousands of them. These objects are characterized by many surprising properties that are not yet understood. For instance, the chemical reactivity of a cluster can change by several orders of magnitude when just one single atom is added or removed. Clusters are promising candidates for novel applications, from catalysts to magnetic storage devices and optoelectronic circuits. The study of clusters in intense X-ray fields will not only provide new insights into their structure and properties, but also result in new technological applications.
The development of laser technology in the past decades demonstrates the potential inherent in understanding the behaviour of small objects in very intense light fields. Today already, photonics – i.e. the use of visible light for instance in communications technology – plays a major role. Especially important in this respect are so-called non-linear effects. These occur for example when two photons of the same wavelength hit a material and transform into one photon of twice the energy. Such non-linear processes are very rare in the X-ray realm and have therefore scarcely been studied so far. The intense X-ray flashes of the European XFEL will enable scientists to systematically investigate non-linear processes in the X-ray range for the first time. Mixed situations in which visible light interacts with X-ray radiation will be of very high interest as well.