Heidelberg 2015 – wissenschaftliches Programm
A 36.8: Poster
Donnerstag, 26. März 2015, 17:00–19:00, C/Foyer
Limits for Light Modulation by Stark Shifting Rydberg EIT and Superradiance in Thermal Vapor Cells — •Harald Kübler, Margarita Reschke, Mohamad Abdo, Alban Urvoy, Robert Löw, and Tilman Pfau — 5. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany
Over the past few years, the usage of atomic vapors has become more and more relevant in technological applications. The demonstration of coherent dynamics on the nanosecond scale  opened the field for high frequency applications.
We demonstrate our progress towards a light modulator based on Rydberg EIT, where the Rydberg state can be shifted by an external RF field. We investigate the limitations on the modulation frequency as well as the limitations on the modulation depth.
One limiting factor in systems with high Rydberg densities is Superradiance. The wavelength of Rydberg to Rydberg transitions can be on the order of 1cm, meaning that a lot of Rydberg excitations are within the volume of one wavelength. These excitations can decay collectively and this can become the dominant decay process. We study the decay dynamics of this process in a thermal vapor cell and compare the experimental results to a rate equation model.
 Huber et al., PRL 107, 243001 (2011)