SFB 652:  Strong Correlations and Collective Effects in Radiation Fields: Coulomb Systems, Clusters and Particles

Subject Area Physics
Term from 2005 to 2017
Project identifier Deutsche Forschungsgemeinschaft (DFG) - Project number 5486320
 

Project Description

In the centre of this Collaborative Research Centre are recently developed technical and physical possibilities which enable to open up new phenomena of the interaction of light (or more generally: a radiation field) and matter. For the first time, in a coordinated research effort, the interplay between the radiation field and the solid state, in particular semiconductor quantum wells and dots, clusters and particles as well as Coulomb systems, will be comprehensively investigated. As radiation sources serve besides different optical laser systems - cw lasers, pulsed lasers from 20 femtoseconds (1 femtosec. = 0,000000000000001 sec.) to nanoseconds (1 nanosec. = 0,000000001 sec.) pulse width, and with extremely high power densities - also the Free Electron Laser (FEL) and the X-ray Free Electron Laser (X-FEL, both at the Hasylab/DESY in Hamburg).
If for example ultra-short laser light pulses hit on a semiconducting material, under suitable conditions electron hole ensembles are formed, which interact with the radiation field in a special way. That is the field of semiconductor quantum optics, in which possibilities for quantum computing or the production of novel quantum states (Bose Einstein condensation) are investigated. In the case of drastically stronger excitation with ultra-intense lasers the state of matter changes from the atomic structure into a dense electron-ion-system (dense Coulomb system). This state is well-known from the inside of the sun and from large planets. Finally the specific excitation of collective effects makes it possible to control the energy absorption from an intensive radiation field, which was demonstrated recently in an impressive way with clusters. The results of these experiments could lead to the development of new lasers.
Thus a characteristic feature in this cutting-edge research field is the presence of a radiation field, which initiates complex and on the microscopic scale connected, i.e. correlated and collective phenomena. On the other hand the radiation field can also be used to identify these correlations. The connection of aspects of correlations and of the radiation field is thus a universal concept of fundamental importance.
DFG Programme Collaborative Research Centres

Completed projects

Applicant Institution Universität Rostock
Participating University Universität Greifswald
Spokesperson Professor Dr. Karl-Heinz Meiwes-Broer