[Seminar] " Solitons, vortices, and quantum solitons in ultracold atomic gases" by Prof. Joachim Brand

Speaker:

Dr. Joachim Brand

Title:
Solitons, vortices, and quantum solitons in ultracold atomic gases

Abstract:

Nonlinear structures in quantum gases can be long-lived due to either topological properties, in the case of vortices, or the abundance of (nearly preserved) conservation laws. In the presence of confining geometries, interesting bifurcation and cross-over scenarios blur the notions of what solitons or vortices behave like. I will discuss these scenarios in the context of solitonic vortices and Josephson vortices. 

But how can we understand solitons microscopically, from quantum-many-body theory? And what kind of effects can we expect when solitons become microscopic and the hosting quantum fluid strongly correlated? As an example I will discuss the Lieb-Liniger model of a one-dimensional Bose gas, where exact quantum dynamics can be utilised to understand solitons as well as quantum effects beyond mean-field theory. 

Brief bio:

Professor Brand originally hails from Germany and obtained his PhD from the University of Heidelberg. After research fellowships at the University of Washington in Seattle and at the Max Planck Institute for the Physics of Complex Systems in Dresden he moved to New Zealand to take up a faculty position at Massey University in Auckland. He is currently Professor of Theoretical Physics at the New Zealand Institute for Advanced Study and principal investigator in the Dodd-Walls Centre for Photonic and Quantum Technologies.