Nonlinear effects occur in many media and in many different configurations. Concerning the medium, we focus on experiments using sodium vapour. The nonlinearity is due to optical pumping. Beside technical advantages (high optical quality, easy variation of parameters over a broad range, high resonant nonlinearity) the benefit of using an atomic vapour is that the equations governing the light-matter interaction can be derived directly from quantum mechanics via the density matrix approach. Regarding the investigated configurations, investigations have been done in most of the situations in which spatial optical structures are known to occur. Since we are interested in the fundamentals, we work in a so-called single-mirror feedback system because of its conceptual simplicity.
The experiment is discontinued but some data analysis is ongoing.
Over the years (1994-2007), many people contributed to the success of these investigations at the University of Muenster (Germany):
- PI: Thorsten Ackemann, Wulfhard Lange
- Postdocs: Ramon Herrero, Yuri A. Logvin
- Postgraduate students: Andreas Aumann, Florian Huneus, Edgar Grosse Westhoff, Matthias Pesch, Burkhard Schaepers, Jens Seipenbusch, Jens Schuettler
- Undergraduate students: Burghard Berge, Monika Boelscher, Marc Feldmann, Benedikt Giese, Andreas Heuer, Volker Kneise, Daniel Rudolph, Jens-Uwe Schurek, Michael Tegeler
- IMEDEA (Palma de Mallorca): Damia Gomila, Pere Colet
- University of Strathclyde: Thorsten Ackemann, Willie J. Firth, Gian-Luca Oppo
We are grateful for funding by the Deutsche Forschungsgemeinschaft and the Deutsche Akademische Austauschdienst.