CQD Special Seminar

19. July 2018 15:00

Konferenzraum 4, 01.106, Physikalisches Institut, INF 226

Composite, rotating impurities interacting with a many-body environment: analytical and numerical approaches

Dr. Giacomo Bighin
IST, Institute of Science and Technology, Klosterneuburg, Austria


The angulon quasiparticle, formalizes the concept of a composite, rotating impurity in a quantum many-body environment and has proven useful in the description of several experimental settings, from ultracold molecules in a BEC to molecules in He nanodroplets. I introduce a diagrammatic formalism, merging Feynman diagrams with the angular momentum diagrams known from atomic and nuclear structure theory, describing angular momentum redistribution in a many-body system. Then, motivated by recent experiments on laser-induced alignment of molecules in He nanodroplets, I introduce a finite-temperature variational approach to angulon dynamics, showing that the far-from-equilibrium dynamical response of molecular impurities can be rationalized in terms of angulons.

 

up

29. Oktober 2025 16:30 Uhr

INF 226, K1-3 (Goldbox)

Exploring many-body physics with extended-range interactions

Dr Pascal Weckesser, Max Planck Institute of Quantum Optics

 PreTalk: “Quantum droplets in Bose-Fermi mixtures”, Olivier Bleu, ITP, Heidelberg University

4. November 2025 14:15 Uhr

Kirchhoff-Institut für Physik, INF 227, Seminar Box 2

Josephson supercurrents and vortex dynamics in binary Bose-Einstein condensates

Dr. Alice Bellettini, Department of Applied Science and Technology, Politecnico di Torino, Italy

Quantum bosonic gases, due to their manipulability, provide the perfect platform for observing macroscopic quantum many-body phenomena. These can be for example quantum vortices (“topological defects”), being the hallmark of superfluidity, or Josephson supercurrents. Such collective effects have been recently employed in the context of quantum simulation and atomtronics. Here, I will present my research on the properties of massive quantum vortices in different configurations, and on vortex-supported supercurrents.
I will go through the inertial effects governing the massive vortex dynamics, to then focus on dipole scattering processes and on Josephson supercurrents as well as self-trapping effects in two- and many-vortex systems. Finally, I will conclude with an overview of the open questions on the topic.
 

contact
Prof. Dr. M. Weidemüller
Physikalisches Institut
Im Neuenheimer Feld 226
69120 Heidelberg
 
06221-54 19470
Ferman Alkasari