Benoit Deveaud-Plédran
Laboratory of Quantum Optoelectronics, EPFL, Switzerland

Date
23 October 2013
Host
Jerome Faist
Title
Vortices and Superfluidity in Exciton-Polariton Condensates
Abstract
Polariton condensates may be created both spontaneously through a “standard” phase transition towards a Bose Einstein condensate, or be resonantly driven with a well-defined initial phase, speed and spatial distribution. Thanks to the photonic component of polaritons, the properties of the quantum fluid may be accessed very directly, with in particular the possibility of detailed interferometric studies. This allows for example to probe the long-range coherence properties of a quantum fluid with unprecedented ease. This also allows testing superfluid properties with great precision in space and time. Here, I will describe the static and dynamics of vortices in polariton condensates, obtained with a picosecond time resolution, in different configurations, including their phase configuration. I will show in particular the dynamics of spontaneous creation of a vortex as well as the dissociation of a full vortex into two half vortices. I will also highlight some of the recent results obtained through the shaping of the system, either using nanotechnology processes, or using all optical means, or both of them. This allows in particular to study superfluid hydrodynamics of polariton fluids.