Erlangen 2018 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

A: Fachverband Atomphysik

A 41: Poster Session IIIa

A 41.7: Poster

Thursday, March 8, 2018, 16:15–18:15, Orangerie

Selfbound quantum droplets — •Jan-Niklas Schmidt, Matthias Wenzel, Fabian Böttcher, Michael Eisenmann, Tim Langen, Igor Ferrier-Barbut, and Tilman Pfau — 5. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany

Strongly dipolar quantum gases enable the observation of many-body phenomena arising from anisotropic, long-range interactions. One example we have observed in our experiment with an ultra-cold quantum gas of Dysprosium is the self-organization similar to the Rosensweig instability in classical ferrofluids. This is observed as modulational instability when tuning the scattering length via narrow Feshbach resonances.

Furthermore we found that the product of the instability is an ensemble of self-bound droplets in a liquid state. This state can only be explained by beyond mean-field corrections arising from quantum fluctuations. In cylindrical harmonic traps, the existance of the modulational instability strongly depends on the trap aspect ratio. We obtain a critical point in the phase diagram representing the lowest trap aspect ratio for which this modulational instability is observed. For lower trap aspect ratios an adiabatic crossover between a BEC and a single droplet state takes place. These results are in good agreement with simulations of the extended Gross-Pitaevskii equation.