Investigations of topological phases for quasi-1D systems 

Tirrito, Emanuele (Date of defense: 2020-07-13)

For a long time, quantum states of matter have been successfully characterized by the Ginzburg-Landau formalism that was able to classify all different types of phase transitions. This view changed ...

Quantum many-body physics with ultracold atoms and molecules: exact dynamics and machine learning 

Dawid Lekowska, Anna Maria (Date of defense: 2022-09-20)

(English) Quantum many-body physics poses a substantial computational challenge resulting from the exponential growth of the wave function complexity and many non-trivial correlations encoded in it. ...

Complex systems for quantum technologies 

Braungardt, Sibylle (Date of defense: 2011-07-12)

Ultracold dipolar gases in optical lattices 

Trefzger, Christian (Date of defense: 2010-04-19)

Esta tesis es un trabajo teórico, en el que estudiamos la física de los átomos dipolares bosónicos ultrafríos en retículos ópticos. Éstos gases consisten de átomos o moléculas bosónicas, enfriados bajo ...

Investigating quantum many-body systems with tensor networks, machine learning and quantum computers 

Kottmann, Korbinian Gebhard (Date of defense: 2022-10-14)

(English) We perform quantum simulation on classical and quantum computers and set up a machine learning framework in which we can map out phase diagrams of known and unknown quantum many-body systems ...

Dynamics of quantum mixtures 

Guenther, Nils Eric (Date of defense: 2021-09-08)

At sufficiently low temperatures, fluids of bosonic particles may undergo a phase transition, below which a Bose-Einstein condensate (BEC) forms. The BEC is one of the most fundamental concepts in ...

Spectral evidence for a condensate of dark excitons in a trap 

Beian, Mussie (Date of defense: 2016-06-22)

Spatially indirect excitons, being composite bosons, are attractive candidates to explore correlated many-body systems. They possess an inherent large electric dipole, a four-fold spin manifold, and can ...

Exact diagonalization studies of quantum simulators 

Raventós Ribera, David (Date of defense: 2019-04-15)

Understand and tame complex quantum mechanical systems to build quantum technologies is one of the most important scientific endeavour nowadays. In this effort, Atomic, molecular and Optical systems ...

A cold-atom approach to topological quantum matter across the energy scale 

González Cuadra, Daniel (Date of defense: 2020-12-11)

The outstanding progress achieved in the last decades to isolate and manipulate individual quantum systems has revolutionized the way in which quantum many-body phenomena, appearing across Nature's ...

Experimental evidence for the quantum condensation of ultracold dipolar excitons 

Alloing, Mathieu (Date of defense: 2014-05-28)

In this thesis, we report experimental evidence of a "gray" condensate of excitons, as predicted theoretically by M. Combescot et al. Most importantly, the condensate is characterized by the macroscopic ...