Wolf-Rüdiger Hannes, AG T. Meier
What is the challenge of my research project? Why am I eager to do it?
As a postdoc in the project A07 of the TRR142 I carry out theoretical simulations of widely non-degenerate stimulated two-photon emission in semiconductors. I assist in the analysis of the measurements and identify optimal parameter choices and fundamental limits for two-photon absorption, stimulated emission, and other nonlinear optical processes. Modeling the interactions of ultrashort light pulses with semiconductors in the femtosecond (10-15 s) time range is demanding, hence I have to use reasonable approximations to make the model solvable by computational methods. The semiconductor-Bloch equations extended by the intraband acceleration terms are my most often used tool. I investigate both perturbative properties such as two-photon absorption coefficients and the non-perturbative response including dynamic saturation effects.
Why did I choose this project?
The light-matter interaction constitutes rich physics even within the semiclassical picture. I find it exciting to figure out how each external parameter influences the observed spectra. I am convinced that a thorough understanding of higher-order processes is crucial for the development of novel nonlinearoptical functionalities such as optical switching.