Parts | Days | Selection | Search | Downloads | Help
Q: Quantenoptik
Q 222: Nichtlineare Optik II
Q 222.4: Talk
Tuesday, March 5, 2002, 17:15–17:30, HS 22/108
Phase-dependent interaction in a 4-level atomic configuration — •giovanna morigi1, sonja franke-arnold2, and gianluca oppo2 — 1Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermannstrasse 1,D-85748 Garching b. Muenchen — 2Department of Physics, University of Strathclyde, Glasgow G4 0NG, Scotland
We consider a four-level atomic configuration driven resonantly by four laser fields in a closed-loop configuration, and study how the steady state depends on the relative phase Φ between the lasers. At saturation, the steady-state of the system depends critically on Φ, and it may exhibit population inversion, or complete destructive interference, such that the occupation of an atomic state is completely empty. We explain the phenomena in terms of Coherent Population Trapping and multiphoton interference, and provide a simple picture for the dynamics. Given the sensitivity of the system on the relative phase between the lasers, we draw analogies with the scheme and an interferometer. Finally, we discuss possible applications, like measuring the phase of a field, realization of non-linear optical devices, and manipulation of the atomic motion.