Seminar "Dynamics of dipolar BECs exposed to a rotating magnetic field and vortex generation in supersolids" Dr. Simeon Mistakidis, Harvard University, USA

Speaker

Simeon Mistakidis
ITAMP postdoctoral fellow
Harvard University

Abstract

We will discuss the static properties and the nonequilibrium dynamics of dipolar Dysprosium Bose-Einstein condensates subjected to a fastly rotating external magnetic field. Relying on the extended Gross-Pitaevskii framework, we account for quantum fluctuations and map out the underlying phase diagram with respect to atom number and relative interaction strengths for various field orientations. Tuning the field orientation (depending on the magic angle) allows selective transitions  from a superfluid to complex supersolid configurations and then to arrays of dipolar droplets characterized by a non-vanishing global phase coherence. These phases occur both in quasi-1D and quasi-2D regimes. Following interaction quenches, across the aforementioned phase transitions, we observe the dynamical nucleation of supersolids or droplet lattices. The inclusion of three-body losses leads to self-evaporation of the ensuing structures, while the rotating magnetic field enables, for fixed values of the relative interactions, an enhancement of the droplet lifetimes. As a next step, we show that solitons facilitate the supersolid character of the dipolar gas. Next, we  monitor the spontaneous generation and interaction of vortices within the supersolid phase aiming to understand their properties, persistence and melting.   

Looking forward to seeing many of you at the seminar.

-Quantum Systems Unit / Busch Unit